: The Northstar Oil Issue



Geno Castellano
01-02-03, 12:04 PM
This discussion will go over the issue of Northstar engines mysteriously losing oil. Most people aren't sure whether the engine is actually leaking or burning the oil. Many people don't find leaks in their driveway. So what's the problem? Has it been fixed in later models? Are there any particular years that are better or worse?

jadcock
01-02-03, 09:24 PM
Usually, the Northstar is just using oil, rather than leaking it out. The Northstar has a very aggressive cylinder hatch pattern, to promote sufficient oiling at high engine speeds (6000 rpm). Unlike many engines, this thing was designed for sustained high rpm use and will run at 6000 rpm all day. The aggressive hatch pattern tends to retain the oil longer than a slicker cylinder wall will.

Naturally, this oil retention keeps the oil up in the piston rings, which is good for lubrication, but it also means that it'll use more than "normal". GM has stated that 1 qt. for 1000 miles is satisfactory. We're used to a "good engine" not using any oil at all, but those engines also need rebuilds after 100,000 miles due to worn out cylinders (less lubrication means more wear). The Northstar is good for many many miles and the oil usage is a small price to pay for this reliability.

Having said that, there's also a tendency for the oil to find its way out of any small and minor imperfection in the block seal area. Not every engine does it. Mine never leaks onto the ground, but it is usually damp down there, meaning that a very minute amount of oil does seep out. It's no big deal and certainly nothing to be concerned about. Rarely does the case half leak drop more than a drop or two every night. If you have a oil leak that's producing a puddle on the ground, it's probably not the case half leak, despite what your Cadillac dealer will probably diagnose it as.

Geno Castellano
01-03-03, 02:22 AM
Thank you for this information! This is good news to me. I have to tell some of my friends to come see this thread. I know Cadillac backed themselves up by allowing more oil that usual anyway. What you said makes great sense, though.. I think I'd rather have it work this way and feel confident that my engine will last longer.

ljklaiber
01-04-03, 04:13 PM
I'll try to pass on the tech of why crosshatch angle , depth and stone selection, is purely a way of seating the ringface.

I have a well used 95 sls with 137k miles. It uses No oil. It drips 2 or 3 drops when run long and hard. I changd at 3k miles including Wix filter i added 6.5 Qt.. (just into the stick area that says ADD!

I have dyno tested synthetics on a Superflo 901, and we still race mineral oil ............changed weekly.
Synth is ok, but definately NOT worth the cost.

Alloy engines appreciate a patient and careful warmup. Aluminum expands over twice as much as iron.

NS is a beauty!

Buy th correct fuel for your yearmodel. I use 93 AMOCO in my 95.

Happy New Year!
ljk

Sevillius
01-05-03, 10:03 PM
Another thanks for Jason's info. I have never heard this "simple" (meaning as a compliment!) explination before.

Paul G.

jadcock
01-05-03, 10:25 PM
Another thing to mention is that oil usage is usually directly related to how hard you run the car. The more time you spend at redline, the more oil you'll normally burn.

Mine's pretty consistent like that. If I drive it easy, it uses hardly any oil at all (ALL engines use some oil). If I drive it really hard during a two or three week period, it'll use a quart or two.

Sevillius
01-05-03, 10:29 PM
Just wondering, Jason....are you a teacher at Tech? Your concise comments on engineering-type topics lead me to think as such.

jadcock
01-05-03, 11:29 PM
No...coulda been...sort of. :)

I just graduated with a Technology Education degree, which prepares me to teach tech. ed. in secondary schools. Courses like the (now somewhat rare) woodshop and metalshop classes to the more common technology-based courses (like construction technology, transportation technology, etc.). I found that, at least at this point in my life, I don't enjoy teaching enough to warrant me being in a classroom. I don't enjoy the art of teaching enough to make a difference for the kids (so I'm staying out, for now).

I'm the project manager at a local engineering firm for their GIS department (Geographic Information Systems). Geography and maps are another one of my hobbies (besides cars/engines). Although my tech. ed. curriculum gave me lots of auto/engineering experience, I've learned a lot of what I know from personal experiences and participating on boards such as these.

Thanks for the compliment, though. I really do enjoy mechanical engineering and internal combustion engines. Just didn't have the discipline in school to do an engineering degree. ;)

ljklaiber
01-06-03, 12:09 AM
I believe it is always a good thing to have the younger folks involved on any dialogue. Us old guys have had our day, and we need to pass on what we can and wish all the young our best.

My best to all of you. Auto racing is the finest sport in the whole damn world.

Carry On!

Devil_concours
01-14-03, 11:48 PM
I have a 97 deville concours that's hitting 95k mi currently on odo
My engine was replaced between 55k~65k because i complained about oil consumption constantly and all their solutions didn't work. Starting last summer my car started to overheat periodically. Once it overheats it will get all the way into red when i'm stopped and temp decreases once i'm moving. This has happened several times since dealer didn't have any answers other then telling me to bring the car back when it's overheating!?! (Work --50mi-- home --15~20mi-- dealer = 65~70mi while overheating).
Currently my car is using more than 3quarts of oil in 800mi. They are currently working on it but i have a feeling that it's not going to be fixed. I think the dealer messed up my ac system too but that's another problem for another day

Anthony Cipriano
01-15-03, 06:03 AM
Can you replicate the over-heating problem when you're at the dealer? 3 quarts of oil in 800 miles is a lot. Is your car under warranty? This was a $3000.00 job when it happened to me but the car was under warranty so I only paid a small deductable...

Devil_concours
01-15-03, 10:37 PM
Originally posted by Anthony Cipriano
Can you replicate the over-heating problem when you're at the dealer? 3 quarts of oil in 800 miles is a lot. Is your car under warranty? This was a $3000.00 job when it happened to me but the car was under warranty so I only paid a small deductable...

what your telling me is to drive 70mi while the car is overheating. Of course not. I usually end up filling the car up with 3~4 gallons of water. I think when the car begins to overheat my coolant comes back through the small hose.

I can smell my coolants when i'm stopped at the traffic light (only when it's overheating). In fact i've seen the coolant pour down underneath the car when i waited for it to cool down in some parking lot.

edit- they did headgasket job for free because according to them, my engine is still under warranty. I suspect that gasket went bad because of all the heating issues. I guess technically car is still under warranty because i've been taking the car to them well before the gasket replacement.

Anthony Cipriano
01-16-03, 01:18 AM
Any possibility of driving into the area of your dealing and kinda sticking around awhile to see if you can replicate the over-heating? That's what I should have said in the first place...

Devil_concours
01-16-03, 02:05 AM
well i didn't get to keep the car long enough to know whether it was going to overheat again since the gasket was replaced. I took the car back for bad spark plug(replaced by them), oil consumption, and ac leak.
so far i haven't got my car back and they want to charge me for the ac leak. There was no ac leak few months ago. There was no ac leak before they started transmission work and gasket exchange. It was after and i suspect that they did something to caused the ac to leak.

Anthony Cipriano
01-16-03, 08:57 AM
This sounds like one of those situations I'd rather never be involved in. I guess the over-heating is just touch and go and you have to hope it's not going to happen again since the gasket was replaced.. And the a/c leak will be very hard to prove. Maybe if you sit and wait for the car to be finished, you could take the old part and see if it was damaged - wherever the leak was. I know waiting is probably not possible, though...

kd4awq
02-12-03, 04:40 PM
GM has a supposed fix for some years of Northstar that involves cleaning the cylinders and piston rings. You squirt a special cleaner into the bores through the spark plug holes, then let the car sit for two hours for the cleaner to soak in between the rings, then vacuum the leftover cleaner out. Then you change the oil (without the filter), drive the car for 20 minutes, then change the oil *and* filter since the oil will now have the gunk from the cylinders. This is a job for a dealer, since the vacuum is a special tool designed just for this job.

Devil_concours
02-12-03, 08:01 PM
i've had that done twice but i don't see the difference in oil consumption before and after then again my car seems to be fubared by the dealer and it drinks more oil than normal north*

Katshot
02-12-03, 08:32 PM
Although Jason has a nice sounding explaination that MAY explain high oil consumption during break-in, I'll stick with ljk.

kcnewell
02-12-03, 10:37 PM
I agree, My experience has been that... If you push'em hard they'll use some oil. If you don't they won't! If you break'em in right they'll use less oil over the life of the engine. I can build engines for guys that can be run hard from the get'go but It's more labor intensive....Katshot, you'll like that! It's a fancy way to say Mo' Money! I like to build them where you have to spend some time breaking them in ( at least 500 miles ) They seem to be a little more user friendly and not use quite as much oil in the long run. The trend as of late in the direction of engines that they claim need no break in period is not beneficial in the long run! It's just one more way to please an already too spoiled public!

rickko
06-24-03, 03:13 PM
This link points to 20 other owners commenting on the same high oil consumption characteristic. Some document their remedies and attempted remedies and experiences with their dealerships:

http://www.carsurvey.org/viewcomments_review_17781.html


..rickko..

ljklaiber
06-24-03, 03:49 PM
This link points to 20 other owners commenting on the same high oil consumption characteristic. Some document their remedies and attempted remedies and experiences with their dealerships:

http://www.carsurvey.org/viewcomments_review_17781.html


..rickko..

Drain hot and change filter. Add NO more than 7 qts...mark the dipstick and add NO MORE OIL . That mark is your reference. forget the dipstick levels. Most NS suffer from overfilling the sump. When the crank touches the oil ..it is an Aero goodbye. If in doubt drop back to 6 Qts. 5.7 liter Chevys do fine on 5. NS is a 4'6. Use a qual mineral til you are satisfied. Then change to synth if you think they are worth it.
A few drops in the driveway is what I get..no significant oil loss and it stays clean for a good while. My 95 sls has 138500 miless onit and runs 199 to 205 in 90 degree weather here in Georgia.

ljk :bouncy:

jadcock
06-24-03, 09:12 PM
Yes, the Northstar will run good on 6 qts, even 5. The "Check Oil Level" message doesn't appear until about 2 qts. low, or 5 total. The system was designed to sustain 1g in cornering, thus the 7 quart capacity. During normal driving, it will run good on 5 qts.

I doubt you see much difference in oil consumption over the life of any given engine. Some engines use a little more than others. Some use as much as a quart per 1000 miles. This is considered normal. Gone are the days of the old 2 valve engine that needs a ring reamer after 150k miles due to excessive cylinder wall wear. The valve guides are designed to seep oil into the cylinders to promote sufficient lubrication on all engines, not just on the Northstar. Called "total loss oiling". In order for oil to lubricate the cylinder walls and piston rings, it will naturally come into contact with combustion pressures. Put an aggressive hatch on the cylinder wall and use 4 valves instead of 2 (and theoretically use twice the oil in the process), and you have the ingredients for very long engine life, in terms of cylinder wall wear, at the cost of some oil along the way.

If your Northstar suddenly uses more oil than normal, you may have varnish in the rings or other deposits. These are often formed from light use. Put the car in 2 and do some full throttle runs to redline and let the engine brake the car back down to 30 mph or so. Then do it again a few times. You'll likely see quite a bit of some pretty gross crud dumping out your tailpipes, and that may be the junk unseating from your rings and you may have just fixed the problem "for free". Continue to flog the heck out of the engine every chance you get and enjoy from there. There is also a ring cleaning procedure used at the dealership involving solvents, if that little trick doesn't solve the problem.

Night Wolf
06-24-03, 11:01 PM
For what it's worth, I heard about the metals used in the block and heads, or something with the N* actually repeled each other, like the actual elements of metals do not bond well, but were used anyway, so over time, they loose their form/bonding power and begin so change in shape (not like what the eye can see, but each molecole, and that is what causes alot of the problems)

when my car (4.9) was drivin about 1500 miles from Florida to NY< it didn't use any oil at all......

elwesso
06-25-03, 12:41 AM
Thats interesting..... I have heard that also, and that seems weird that they would still use it..... oh well, as long as it lasts through the warranty period, the heck with what happens after that!

BeelzeBob
06-25-03, 09:38 AM
If your Northstar suddenly uses more oil than normal, you may have varnish in the rings or other deposits. These are often formed from light use. Put the car in 2 and do some full throttle runs to redline and let the engine brake the car back down to 30 mph or so. Then do it again a few times. You'll likely see quite a bit of some pretty gross crud dumping out your tailpipes, and that may be the junk unseating from your rings and you may have just fixed the problem "for free". Continue to flog the heck out of the engine every chance you get and enjoy from there. There is also a ring cleaning procedure used at the dealership involving solvents, if that little trick doesn't solve the problem.

That sounds like the reason my dealer told me to 'push' the car hard once every week or so...

jadcock
06-25-03, 07:52 PM
For what it's worth, I heard about the metals used in the block and heads, or something with the N* actually repeled each other, like the actual elements of metals do not bond well, but were used anyway, so over time, they loose their form/bonding power and begin so change in shape (not like what the eye can see, but each molecole, and that is what causes alot of the problems)

when my car (4.9) was drivin about 1500 miles from Florida to NY< it didn't use any oil at all......

Hmm...I've never heard that one. The Northstar is an all-aluminum engine with steel cast-in cylinder liners. Very very robust. You should find almost zero cylinder wall wear, even after 100k miles. Everyone thinks that if an engine that uses any oil at all, it's gotta be crap "because the 350 in my Camaro didn't burn any". Well, the 350 in the Camaro had slick cylinder walls and had to be oversized after 80,000 miles too...

It makes sense that a 4.9 would use less oil than a Northstar would. Fewer valves means less oil lost through the total-loss oiling concept that I mentioned earlier. Also, the 4.9 doesn't have (to my knowledge), the plateau hone process the Northstar uses (it has smoother cylinder walls). But highway driving is very easy on any engine in general. If you drive all highway miles, you should use very little oil, even with a Northstar. I just ran a 2000 mile trip from North Carolina to Michigan and back and used no measurable oil. My engine is pretty average as far as oil consumption goes. If I drive on the highway a lot, it doesn't use much at all (again, no measurable loss). If I really lay on it all the time, it'll use about a quart every 1000 miles.

jadcock
06-25-03, 07:55 PM
That sounds like the reason my dealer told me to 'push' the car hard once every week or so...

Yes sir. But let's not get into the discussion we had a while ago about whether or not it's "good" to push an engine. :D

lbgraf
07-11-03, 12:51 AM
This discussion will go over the issue of Northstar engines mysteriously losing oil. Most people aren't sure whether the engine is actually leaking or burning the oil. Many people don't find leaks in their driveway. So what's the problem? Has it been fixed in later models? Are there any particular years that are better or worse?

Hi Geno,

I noticed a few weeks ago on a 2150 mile round-trip, with total of 4 people including myself driving, all our luggage etc., that my '96 DeVille with 34,000 miles used about one quart during the trip. At first I was slightly concerned because the engine is dry as can be top and bottom. Then I thought about the NorthStar having the 7.5 quart capacity (including filter) and decided one reason the engine has this large an oil capacity is for exactly the reason given in this thread... the NorthStar is designed this way by the engineers to build in enough capacity to get most drivers through 3000 to 5000 mile intervals without damage, even if a couple quarts down by then. I'm the type that always watched the dipstick so close that I would add 1/2 quart at at time - just to keep the engine at full oil capacity, but not overfilled. It's good to see that the cross-hatch design of the NorthStar block keeps a little more oil film between the rings and cylinder walls - to extend overall engine life and enable higher rpms at the same time. I've been in the truck & car business for nearly 40 years, as parts manager and auto sales, so I've seen and heard about as many stories as you can imagine. I've only had the DeVille since March, but am looking forward to many more miles of enjoyment.

Lee

mechanicatlarge
07-21-03, 07:58 PM
This link points to 20 other owners commenting on the same high oil consumption characteristic. Some document their remedies and attempted remedies and experiences with their dealerships:

http://www.carsurvey.org/viewcomments_review_17781.html


..rickko..

I hear lots of speculation but no real detective work. WHAT do the valve covers look like on the inside? Has any one preformed a hot engine leak-down test? (I'm not talking about a compression test)
How about pulling the dipstick out with engine idleing. Go find a good lawn mower mechanic an get his views on aluninum engines, he been working on them for years now. Thanks

loisalynn
07-26-03, 11:34 PM
This discussion will go over the issue of Northstar engines mysteriously losing oil. Most people aren't sure whether the engine is actually leaking or burning the oil. Many people don't find leaks in their driveway. So what's the problem? Has it been fixed in later models? Are there any particular years that are better or worse?


It's mainly the 1997, but not exclusively. The Northstar leaks oil, not necessarily on the floor, but into the engine. I HOPE they've improved, but at less than 48,000 miles on my 1997 ETC, I had to have a $1,200 repair to fix the oil leak (of which Cadillac paid 1/2, even though my car was 1 month out of warranty).

elwesso
07-27-03, 01:18 AM
This thread was directed towards the northstars using of oil....... Apparently every 3000miles the cars can use upto 3 quarts....... Sometimes more....

And the leak you were referring to is the case half leak...... That is notorious to all northstar years, from 93 on....... It has improved, but there is still leaky engines coming from the factory now.....

becky Bailey
08-06-03, 01:14 PM
This discussion will go over the issue of Northstar engines mysteriously losing oil. Most people aren't sure whether the engine is actually leaking or burning the oil. Many people don't find leaks in their driveway. So what's the problem? Has it been fixed in later models? Are there any particular years that are better or worse?

I have a 97 DeVille and it has been consuming oil since about 30,000 miles. In August of 2003 they are replcing the piston rings, and they say this will solve the problem. Many newer models including 2003 engines also have them problem. Cadillac told me that the problem was not detrimental to the engine so there was no need to tell new buyers or anyone else about the problem. It has been a major inconvenience for me and some people who were unaware of the problem did not know to check their oil between oil changes. If you run low on oil it can damage the engine. Mine is about three quarts every 3,000 miles.

becky Bailey
08-06-03, 01:17 PM
Yes, the Northstar will run good on 6 qts, even 5. The "Check Oil Level" message doesn't appear until about 2 qts. low, or 5 total. The system was designed to sustain 1g in cornering, thus the 7 quart capacity. During normal driving, it will run good on 5 qts.

I doubt you see much difference in oil consumption over the life of any given engine. Some engines use a little more than others. Some use as much as a quart per 1000 miles. This is considered normal. Gone are the days of the old 2 valve engine that needs a ring reamer after 150k miles due to excessive cylinder wall wear. The valve guides are designed to seep oil into the cylinders to promote sufficient lubrication on all engines, not just on the Northstar. Called "total loss oiling". In order for oil to lubricate the cylinder walls and piston rings, it will naturally come into contact with combustion pressures. Put an aggressive hatch on the cylinder wall and use 4 valves instead of 2 (and theoretically use twice the oil in the process), and you have the ingredients for very long engine life, in terms of cylinder wall wear, at the cost of some oil along the way.

If your Northstar suddenly uses more oil than normal, you may have varnish in the rings or other deposits. These are often formed from light use. Put the car in 2 and do some full throttle runs to redline and let the engine brake the car back down to 30 mph or so. Then do it again a few times. You'll likely see quite a bit of some pretty gross crud dumping out your tailpipes, and that may be the junk unseating from your rings and you may have just fixed the problem "for free". Continue to flog the heck out of the engine every chance you get and enjoy from there. There is also a ring cleaning procedure used at the dealership involving solvents, if that little trick doesn't solve the problem.
That did not solve the problem fo rmy car.

Devil_concours
08-06-03, 11:56 PM
no matter what my previous oil consumption rate was, new engine doesn't seem to use up as much as before.

majax
05-09-04, 12:50 AM
I want to buy a 96 STS with 38,000 miles. Is htis oil thing something to really worry about? Also is this a reliable car?

airbalancer
05-09-04, 08:17 AM
Have a 99 STS just change the oil ( computer indicated it was time to change oil)after about 6000 miles and oil need only to top up . This amout is normal for any car

Anthony Cipriano
05-10-04, 02:06 PM
I want to buy a 96 STS with 38,000 miles. Is htis oil thing something to really worry about? Also is this a reliable car?

I wouldn't expect you would have any problems with oil consumption with that car. The Northstar engine will characteristically use a little more oil than some other engines but that's not a sign of the engine failing or of anything wrong. There's no final answer on the oil consumption issue.

A comment was made about the variance in oil consumption on Northstar engines being more of a concern than the actual consumption of any given engine - thus the following comments.

Good point about the difference in consumption....

The real issue is the limitations of the production tolerances on the honing process for the cylinder bores. Size is no problem - they're all dead nuts. Surface finish is the issue. It's imperative that the "smoothest" possible surface finish from the process retain enough oil to not starve the top rings under continuous heavy load and high RPM. Unfortunately, to make the smoothest possible surface finish "rough" enough to retain oil, the resulting "roughest" or most aggressive surface finish the process is then capable of will contribute to a 1000 miles per quart or worse.

There's really no magic here. All the automakers have access to the same honing process and honing equipment manufacturers. Thus, they're all "stuck" with the same variation in production. As engine specific outputs have risen and the operating RPM of the engines have risen over the years all the engine makers have gone to a more agressive surface finish for proper oil retention. And all run into the same situation with variation in oil economy. If you do some reading and research you'll find that all engine makers will state that roughly 1000 miles per quart is "acceptable" or "normal" in some fashion.

Not to say that the 'average" engine gets that oil economy but an engine that gets 1000 miles per quart will have absolutely nothing wrong with it at disassembly and inspection.

The fact is that the engines that tend toward the high end for oil consumption seem to look the best at high mileage whether it's the higher oil supply to the top of the piston or the frequent spiking of the oil in the sump with fresh additives due to more frequent adds (or both) is up for debate.

Back in the "old days" of 350 cubic inch engines that made 180 horsepower it was entirely possible to make the cylinder walls mirror smooth and the engine would live and use virtually no oil. It won't work today with the horsepower over 1 horsepower per cubic inch and RPM up to 6000 continuously and 6500rpm shift points. The top rings wont take it without microwelding to the ring lands of the pistons.

The honing operations have received many improvements over the years as technology in the honing arena improved. Today, diamond stones with a water based honing coolant is the norm for long life stones that don't change over time. The older processes with vitrous stones and honing oil change significantly as the stones break in and wear and the stones had to be changed frequently as they wore out. So each hone was going through a continual cycle of break-in and wear out of the stones. Generally on a V8 two cylinders on each bank are honed at a time and then the other two are done in the next station by two other stones. So any given engine has 4 different honing stone sets in the differenct bores. Depending on what the life of the stones is and when they were being replaced there can be some variation in the surface finish (in regards to oil consumption) from cylinder to cylinder and bank to bank. Usually when the stones are new they make the most aggressive cut and leave the most aggressive pattern. The stones get smoother as they wear and the pattern gets less agressive. All the stones are "broken in" in initially on scrap blocks but there is obviously some change in the next several hundred blocks.

To put things in perspective, an average engine builder might hone one or two engines a week. A major NASCAR engine builder might do 400 or 500 engines a year. Every day the engine plant that makes Northstar engines hones 1000 blocks - that's 8000 bores. And even more are done on a lot of days. The 1000 number is very loose. There's a great deal of process control placed on the cylinder wall surface finish but the inherent variences in the process will certainly lead to a considerable difference in oil economy in some engines - and absolutely nothing will be wrong with them.

Personally, if I could pick my engine from the line, I would go for one that uses about 1500 per quart. Seriously.

One thing that was done on the original Northstar engines was a process called plateau honing. In this process the cylinder walls are "marked" with a very agressive hone that leaves fairly deep scratches. The high points of the hone pattern are then smoothed with a second hone plateauing off the tops or tips of the "peaks". Under a micorscope this looks like a flat platueau with relatively deep, narrow crevices for oil retention. This process worked very well for oil retention and durability but was inconsistent for oil consumption to some extent. The current process has been improved with a more conventional hone that is not deliberately plateaued and is more consistent. Plus it uses the diamond stones that last far longer and are much more consistent over time.

The other thing that the modern engines sacrifice oil consumption for is friction. The thinner rings and lighter spring load rings are desireable for power, sealing of compression, less friction and lighter mass for less ring flutter at high speeds. Unfortunately, there's no free lunch here, and the lighter rings let a little more oil by.

The 2000 and later Northstar engines get hard anodized top ring lands to resist pound out and wear since the ring lands were moved closer to the top of the piston. One unfortunate side effect of the hard anodizing is the microscopic "pebbly" finish of the anodizing that tends to cause lack of seating of the SIDE of the ring to the SIDE of the ring land. This pebbly area will retain oil and cause oil consumption until the anodizing is polished smooth as the rings "break in" to the ring lands. The anodizing is hard, however, so that is why the "drive it like you stole it" advice works , particularily on later Northstars, to ensure good break in and sealing for less oil consumption. Many of the oil consumption complaint engines that have been analyzed at the factory had the anodizing on the piston ring lands virtually unscathed - as in never broken in due to gently driving and babying. The engine likes heavy loads, high RPM to break in completely.

The heavy load/high RPM also promotes ring rotation on the piston to keep the rings freed up and mobile. The oil comsumption complaints from the older Northstars typically come about due to ring sticking in the ring lands due to carbon buildup and the rings gradually getting stuck in place. they have to move to work. Keep them exercised.

Anthony Cipriano
05-10-04, 02:11 PM
For what it's worth, I heard about the metals used in the block and heads, or something with the N* actually repeled each other, like the actual elements of metals do not bond well, but were used anyway, so over time, they loose their form/bonding power and begin so change in shape (not like what the eye can see, but each molecole, and that is what causes alot of the problems)

when my car (4.9) was drivin about 1500 miles from Florida to NY< it didn't use any oil at all......

I know this was an old comment but since someone dredged this up I'm sure others are reading it. The idea of "metals repeling each other" or "not bonding" or anything is just not true.

The Northstar block and head castings are both aluminum so they're common materials. The cast iron cylinder liners are cast into place in the aluminum block. Iron cylinder liners do not "bond" metalurgiacally with the aluminum. The design of the OD of the liners is designed to mechancilly lock into the aluminum casting of the block as the aluminum solidifies so they do not rely on any sort of "bonding" to seal or stay in place. The guys that engineered the engine realize fully well the mechanical and metallurgical properties of aluminum and iron and the engine is designed to make the proper use of the materials' properties.

ilovemyv8srx
05-13-04, 08:19 PM
I special ordered my 1998 Concours in 1998. It has the same problem that I need to add motor oil every 1,500 miles if I drove at high speed (between 70 and 90 mph). When I drove from Houston to Boston two years ago, I realized the car was not running smooth. After checking the oil at the gas station, I noticed the problem. Since then I keep a quart of 10W30 motor oil in my the car and check the oil level more often. But I find the situation only appears when I drove for a long distance at a high speed.

This is a special order car with towing package that has a transmission cooling package for towingup to 3,000 lb. In fact, I always order my car with this package. It was a less than $200 option. I wonder why GM not making it as a standard equipment. My car runs really great and it has 110,000 miles and has no major problem. I change motor oil every 3,000 miles at the dealer. It charges $25 to do motor oil change.

My 1986 Serville had 220,000 miles when I trade it for the 2001 Catera. But my 1984 MB 300D still the best according to the milage because it has over 290,000 miles. But, there is no comparion when it comes to the comfort. I don't mind adding motor oil if I have to. But I also realize it has something to do with my driving habit.

I am really lucky!:bouncy:

JohnnyO
05-14-04, 11:27 AM
The oil comsumption complaints from the older Northstars typically come about due to ring sticking in the ring lands due to carbon buildup and the rings gradually getting stuck in place. they have to move to work. Keep them exercised.

:coolgleam Which is why I run Mobil 1 in my parents' Cadillacs. In my layman's opinion, a full synthetic ought not carbon up rings. (Hey, my degrees are in economics, not engineering, but I figure it can't hurt.) Started that with mom's at 25k miles but I guess it's is going to be an oil-burner no matter what. I changed out dad's factory fill at 3400 miles and put in the Mobil 1.

Anthony Cipriano
05-14-04, 01:48 PM
:coolgleam Which is why I run Mobil 1 in my parents' Cadillacs. In my layman's opinion, a full synthetic ought not carbon up rings. (Hey, my degrees are in economics, not engineering, but I figure it can't hurt.) Started that with mom's at 25k miles but I guess it's is going to be an oil-burner no matter what. I changed out dad's factory fill at 3400 miles and put in the Mobil 1.

Even synthetics will break down in the temperatures in the ring belt area. So there's no guarantee of eliminating ring belt deposits.

The best insurance against ring belt deposits and carbon buildup is frequently exercising the rings to keep them mobil and the ring lands free and clear. High RPM and WOT operation is the key. Occasionally airing it out does much more than synthetic oil could ever achieve.

JohnnyO
05-14-04, 08:57 PM
High RPM and WOT operation is the key. Occasionally airing it out does much more than synthetic oil could ever achieve.

:coolgleam They're my parents' cars, but every chance I get.... :burn:

infin1ty
05-16-04, 12:43 AM
You just have to love an automobile that sounds and feels so good when it is getting its required dose of WOT. It is one sweet machine!

ddmorgan
08-17-04, 06:51 PM
I just recently bought a 98 Seville SLS w/ 67k miles. The car had a few cosmetic problems but seemed to run well (good power, good exhaust, tight steering, etc.). The dealer changed the oil when I bought it and I checked the oil at 67800, noticed one quart low. Then checked again at 68600, again one quart low. Each time I added a quart. I was very relieved to see the discussion here and to see that others had the same issue and I didn't get a rotten apple. Thanks for the discussion.

JohnnyO
08-20-04, 02:52 PM
:coolgleam There is a ring cleaning procedure the dealer can do, but on my mother's car it didn't make any difference. My dad's '04 seems to not use any oil.

STS 310
08-20-04, 05:54 PM
Interesting thread http://www.cadillacforums.com/forums/showthread.php?t=19510

Anthony i did read your post earlier in this thread here, but does the post listed above have any merit with regards to the issue?

Anthony Cipriano
08-23-04, 05:27 PM
Interesting thread http://www.cadillacforums.com/forums/showthread.php?t=19510

Anthony i did read your post earlier in this thread here, but does the post listed above have any merit with regards to the issue?


Are you asking if running the Northstar a little low on oil (7 quart fill vs 7.5 - or keeping it at the ADD mark all the time) will reduce oil consumption?

If so, then yes, typically keeping it a little low will help. The oil consumption is very sensitive to oil level particularily as it's overfilled even slightly. The oil level in the sump is very close to the rotating/reciprocating parts so overfilling it will cause aeration of the oil and cause some to be pulled out the PCV.

The Northstar is set up to have 7 quarts in the sump (7.5 fill with a dry filter at a change) to keep the oil pickup covered under severe corning situations. Unless the car is on the track the oil level can be lowered significantly with no concern whatsoever.

Most of the time the oil consumption is aggravated due to constant overfilling (always topping off to the full mark) or filling to the full mark cold which results in an overfilled condition when the engine is hot and the oil expands slightly. Keeping it at the add mark just assures that it's not "too high" even if the stick is a little off or the level is checked/filled cold.

It isn't a big deal and isn't the only explaination for oil consumption but it's directionally correct to minimize the oil consumption to keep the oil level as low as practically possible given the operating requirements of the system.

Randy_W
08-23-04, 10:34 PM
My '96 has never used any oil at all, it has 90k now. Maybe that WOT bit does help, I'll try it more often, if that's possible! :rolleyes:

Mofoco
09-30-04, 11:15 PM
BUMP

Ok, has anyone tried the fixed orafice PCV Valve to see if that is the fix to the oil consumption. GM has the same problem with many of its 96 to current year vehicles with high oil consumption. The GM part # is 12572717 the dealer you are working with may not know that this may be a fix.

The reason I see GM not admiting to the problem is the "cost" of replacing millions of PCV Valves at how much $ ?????

I do not buy into the lubrication theory, if in fact it is burrning that much oil, how long are the cats going to last???? How long are the O2 sensors going to last????

If you run the engine hard it pumps the oil to flood the valves and cams in the valve covers, then the high vacumn of the PCV valve relieves the engine of the oil vapors at a higher rate, therfore the loss of oil. Some of the castings that return the oil back to the oil pan may not be completely clear allowing more oil to stay in the heads longer on some cars so you have different mileage to loss ratio from car to car, and driver to driver due to driving habits.

Somebody :lies:

Anthony Cipriano
09-30-04, 11:41 PM
BUMP

Ok, has anyone tried the fixed orafice PCV Valve to see if that is the fix to the oil consumption. GM has the same problem with many of its 96 to current year vehicles with high oil consumption. The GM part # is 12572717 the dealer you are working with may not know that this may be a fix.

The reason I see GM not admiting to the problem is the "cost" of replacing millions of PCV Valves at how much $ ?????

I do not buy into the lubrication theory, if in fact it is burrning that much oil, how long are the cats going to last???? How long are the O2 sensors going to last????

If you run the engine hard it pumps the oil to flood the valves and cams in the valve covers, then the high vacumn of the PCV valve relieves the engine of the oil vapors at a higher rate, therfore the loss of oil. Some of the castings that return the oil back to the oil pan may not be completely clear allowing more oil to stay in the heads longer on some cars so you have different mileage to loss ratio from car to car, and driver to driver due to driving habits.

Somebody :lies:


You must not know how a PCV valve operates. It's nothing but an orifice and a one way "check valve". The flow through the PCV system flows in two directions and in two fashions. When the engine is operating in a throttled condition (with manifold vacuum present) the suction of the manifold vacuum pulls crankcase vapors through the PCV valve and into the intake manifold. The amount of flow is determined by the vacuum and the size of the orifice in the PCV valve. The vacuum "closes" the valve so the only flow through it is through the orifice. When the engine is run hard - ie. at full throttle - there's no manifold vacuum. So that part of the system is not functional. There's no active flow through the PCV valve due to the lack of vacuum. Due to the lack of vacuum, the PCV valve "opens" so that there's a larger flow area available so that crank case pressure (which is slightly positive at heavy throttle) can escape. The fresh air side of the PCV that draws clean air into the crankcase from the air cleaner is always open so that clean air flows into the crankcase due to the vacuum through the PCV valve at part throttle. The fresh air side turns into a vent for positive crankcase pressure at full throttle so, in effect, the direction of flow reverses when the fresh air side is acting as a vent.

The idea that the engine is pulling more oil through the PCV at heavy throttle openings is really not possible as there's no vacuum to "pull" oil through the PCV valve. In any case, the orifice in the PCV valve is the same size as the fixed orifice installed on 2001 and later engines in place of the PCV so the function is exactly the same.

The fixed orifice was installed in place of the PCV valve to meet the requirements of the ODB2 diagnostics. This was an EPA/government mandated change to incorporate a PCV diagnostic onboard so as to be able to diagnose and inoperative PCV system. All manufacturers did this. It was not done to "fix" or "replace" and ineffective PCV system or anything like that at all. It was done to make the PCV diagnostic work - that's all. And since it's the same size orifice as the PCV valve had anyway, functionally, it's the exact same thing.

Blocked oil drainbacks? You must have never had a Northstar engine apart to say that. The oil drainbacks from the heads are very extensive. There are several separate drainbacks all along the engine block on each side for the length of the head. Even if one or two were blocked mysteriously the others could easily handle the oil to the heads and the large opening at the front of the heads (where the cam chains are) would allow drainback of most any volume of oil before it could reach any critical level in the cylinder head cavity. It's just not possible.

So, nobody is lying. But somebody is proposing a conspiracy that just doesn't exist and isn't technically feasibly if you know the facts.

Mofoco
10-01-04, 01:40 AM
Since this is not just a Cadillac issue, the link shows the 2 PCV valves. http://www.gm-trucks.com/IAR_pcv.shtml
So the 5.7 GM engine that uses a quart every 1800-2000mi. is supposed to also.
Does your NS have the fixed orifice? or the Rattle? What do you think about the Catalytic Converters? How long will they last?

CadiJeff
10-01-04, 02:26 AM
( So you have had several engines apart? It may not be the problem but the oil pump moves a very large volume of oil, that oil is flung everywhere. The oil as a liquid cannot come in contact with the PCV valve or vent directly, but vapors go fast. )

LOL You are new here right?
FYI Anthony Cipriano works on Northstars every day and if you check his other posts he seems to have plenty of experience w/ the northstar engine and many other aspects of cadillacs as far back as the ht4100 engines. trust me when I say that he knows his stuff.

Anthony Cipriano
10-01-04, 12:19 PM
Since this is not just a Cadillac issue, the link shows the 2 PCV valves. http://www.gm-trucks.com/IAR_pcv.shtml
So the 5.7 GM engine that uses a quart every 1800-2000mi. is supposed to also.
Does your NS have the fixed orifice? or the Rattle? What do you think about the Catalytic Converters? How long will they last?



Yes, I've "had the PCV valve apart" and can tell you that the orifices are the same size. I also know the engineer that has designed and released responsibility for the part - which is easier than taking the PCV valve apart to find out the orifice size.

Yes, I've had "several" Northstar engines apart.

Several of your comments correcting me could use some explaination.

My explaination of how the PCV works isn't "close to correct" - it IS correct. The valve "opens" (that's the rattle you hear when you shake the valve - the valve opening) when the vacuum is low (heavy throttle) and the pressure in the crankcase from heavy throttle operation can escape through the valve or through the fresh air vent (backflow).

The fresh air vent isn't "at high vacuum". Atleast not in any modern induction system with a low restriction air cleaner. For the fresh air vent to be under "heavy vacuum" the air cleaner would have to be very restrictive which isn't good for horse power. You can prove this yourself with a vacuum gauge on the intake. Watch the vacuum at full throttle (should be zero) and watch it as the RPM rises to the full throttle shift point. The vacuum will stay at or very near zero. You might see 1 in Hg vacuum at 6500rpm full throttle - not much vacuum at all - and that would be the vacuum on the fresh air side of the PCV system. So, the explaination is correct. The fresh air side acts more as a vent than any thing. True, there will be a little more flow through the fresh air side due to the SLIGHT vacuum but that's really negligable.

If there WAS a lot of oil pulled through the fresh air side you'd see the air cleaner full of oil. You don't so it isn't.

The oil pump flows 12 gallons per minute of oil (to be be precise) at 6000rpm in the Northstar. Yes, that's a lot of oil - but - not all of it goes to the heads. Very little of it goes to the heads, actually, as the feeds to the heads are orificed at the head gasket to limit oil flow to the heads. The oil that's in the heads is flung off the cam lobes, etcetera - not spewed out by the oil pump pressure.

You mention the vapors "going fast". Where to? The oil vapor and crankcase mist and vapor only goes through the PCV valve as fast as the orifice allows - which isn't very fast. The orifice is designed to slow the flow through the PCV system when it's under vacuum so that the oil separation in the cam covers can work correctly. No matter what the engine speed or vacuum level is at the PCV flow is relatively constant. True the vapors are whipping around pretty good inside the engine but the flow through the PCV to the intake manifold is actually very slow and controlled.

You have your units mixed up. Intake manifold vacuum is generally expressed in inches of mercury ie. 22 in Hg. NOT in pounds per square inch gauge (PSIG) as you indicate. True, a heavy decelleration creates 22 in Hg. vacuum (or more) but the RPM is coming down fast at that point and few engines, especially on the street with an automatic transmission, spend any time in that condition. As soon as you lift, the transmission upshifts so there's very little heavy decelleration time on the engine in practical use.

With the modern oils the cats last fine with some oil consumption. I've seen very high mileage engines with oil consumption of 1000 miles per quart that still easily pass emissions. The fact that many forum members have emission tested their cars regularily with very few complaints about passing the tests indicates that the cats and emission systems are doing fine even at well over 100,000 miles.

If you want to look at the oil drainbacks yourself look at the picture in the thread about replacing head gaskets. The three oil drainbacks on the right hand side of the block are clearly visible. Those are the three large bores on the outside of the block that go from the heads to the bottom of the oil pan. there are four on the other side in addition to the large cavity at the front of the heads. Not likely to plug as you can see in the picture - and this is a used engine with a lot of miles on it. http://www.cadillacforums.com/forums/showthread.php?t=21632

The PCV ports in the cam covers are heavily baffled for oil separation and separation of the oil mist. They're pretty effective. They can be overwhelmed with oil mist if the oil level is overfilled and the crank starts to hit the oil and create a LOT of suspended oil - but that's why the Northstar is always recommended to not be overfilled at all. And most people find they get a little better oil economy over the long run by running the oil level on the add mark instead of the full mark as has been described and recommended many times in the past on the forum.

You're completely misunderstanding the pictures of the chevy truck PCV valve you mentioned. THAT isn't the orifice for the PCV flow that you're looking at in the picture. The modified service valve has the smaller hole in the bottom to protect the actual PCV valve/orifice inside the canister from splash. Apparently, in that engine, there was an issue with liquid oil reaching the PCV valve itself (past the baffling in the rocker covers) so the smaller hole was added to the canister to shield the PCV orifice itself. You're comparing apples to oranges. That isn't the orifice being discussed and that's a completely different engine, PCV system and problem.

Mofoco
10-01-04, 10:25 PM
( So you have had several engines apart? It may not be the problem but the oil pump moves a very large volume of oil, that oil is flung everywhere. The oil as a liquid cannot come in contact with the PCV valve or vent directly, but vapors go fast. )

LOL You are new here right?
FYI Anthony Cipriano works on Northstars every day and if you check his other posts he seems to have plenty of experience w/ the northstar engine and many other aspects of cadillacs as far back as the ht4100 engines. trust me when I say that he knows his stuff.

You see the post count! now 3 :) I would say new here! LOL
I am happy to see such a wealth of info here. Eloquence is not my strong side, I am more like a bull in a china closet, I can break an anvil with a rubber mallet. :thumbsup:

Thanks for the Info Anthony, Especially the Cats and Emissions. :worship:
I must read all posts, and post in a year or two.

brown328
01-12-05, 05:27 PM
I have had three NS Cad's. that engine is the greatest. gladly put in 2 quarts per 3000 oil change. RIckko keep up the good work. you saved me a bunch on telling me how to install a window motor. Thanks
dave

baconn_1
01-13-05, 10:11 PM
DON'T BUY A NORTHSTAR! NOT ONLY DO THEY USE OIL " A QUART PER THOUSAND MILES". That's what they told me was normal too.....That is BS!. To me that means somehthing is wrong in the design.....Do yourself a favor, check the threads on not only the oil consumption but the overheating of the Northstar.....Get yourself an owner's manual for a Northstar engine...it states how the Northstar knows how to automatically shut down half the engine when overheating and go into "limp along mode". Why would they put that in the design of a vehicle? Answer is: they didn't. The northstar not only burns oil, it overheats and in both instances GM tries to tell you it's designed that way....Well, if I am paying 45k+ for a car, it better not burn oil or overheat....I dumped both of my caddy's (Sedan De Ville and Eldorado) and bought a Lexus and a Honda. Have never been happier!!!!!!Screw Cadillac...buncha liars.... Don't take my word for it....search the threads and google and listen to all the others having the same issues...

Spyder
01-15-05, 12:40 PM
Nice to meet you too! Welcome to the forums, eh. :)

ellives
01-15-05, 01:18 PM
DON'T BUY A NORTHSTAR! NOT ONLY DO THEY USE OIL " A QUART PER THOUSAND MILES". That's what they told me was normal too.....That is BS!. To me that means somehthing is wrong in the design.....Do yourself a favor, check the threads on not only the oil consumption but the overheating of the Northstar.....Get yourself an owner's manual for a Northstar engine...it states how the Northstar knows how to automatically shut down half the engine when overheating and go into "limp along mode". Why would they put that in the design of a vehicle? Answer is: they didn't. The northstar not only burns oil, it overheats and in both instances GM tries to tell you it's designed that way....Well, if I am paying 45k+ for a car, it better not burn oil or overheat....I dumped both of my caddy's (Sedan De Ville and Eldorado) and bought a Lexus and a Honda. Have never been happier!!!!!!Screw Cadillac...buncha liars.... Don't take my word for it....search the threads and google and listen to all the others having the same issues...


And how long have you owned those Lexus and Honda dealers anyway?

dkozloski
01-15-05, 04:51 PM
Some people should not be allowed near "sheenery".

Ralph
01-15-05, 05:16 PM
DON'T BUY A NORTHSTAR! NOT ONLY DO THEY USE OIL " A QUART PER THOUSAND MILES". That's what they told me was normal too.....That is BS!. To me that means somehthing is wrong in the design.....Do yourself a favor, check the threads on not only the oil consumption but the overheating of the Northstar.....Get yourself an owner's manual for a Northstar engine...it states how the Northstar knows how to automatically shut down half the engine when overheating and go into "limp along mode". Why would they put that in the design of a vehicle? Answer is: they didn't. The northstar not only burns oil, it overheats and in both instances GM tries to tell you it's designed that way....Well, if I am paying 45k+ for a car, it better not burn oil or overheat....I dumped both of my caddy's (Sedan De Ville and Eldorado) and bought a Lexus and a Honda. Have never been happier!!!!!!Screw Cadillac...buncha liars.... Don't take my word for it....search the threads and google and listen to all the others having the same issues...

:hmm: :helpless:

an01sts
01-16-05, 12:14 AM
Would this happen to be the guy who blew op 5 engines in less than 10 blocks and blames it on Cadillac's design?

Would this happen to be the guy who claims that the n/star water pump is positioned too high on the engine; as a result, if the coolant level drops half way, the water pump can no longer pump coolant?

And this idiot, who lacks basic understanding in hydralic laws and basic engine design, is supposed to be an engineer?

If this isn't the the idiot of whom I mention, that's fine. Everyone is entitled to his or her opinion. A common sense opinion would be, simply, just don't buy any more Cadillacs.

If this the idiot of whom I refere, s/he might want to keep it :canttalk: because I'll put the idiot's information on the board, and show everyone what an incredibally stupid 5-engines-in-less-than-10-blocks idiot is.:bouncy:

Wtf! Go ahead, because I might do it anyway if I get board enough.

Spyder
01-16-05, 07:22 AM
I'm lost here... ... ... and ya spelled bored wrong. :-P

Pjs
01-16-05, 01:17 PM
DON'T BUY A NORTHSTAR! NOT ONLY DO THEY USE OIL " A QUART PER THOUSAND MILES". That's what they told me was normal too.....That is BS!. To me that means somehthing is wrong in the design.....Do yourself a favor, check the threads on not only the oil consumption but the overheating of the Northstar


http://www.cadillacforums.com/forums/attachment.php?attachmentid=5284

Go look @ that picture of one of my cylinders at 138K and then tell me there is something wrong with the design of this engine. I used to call my SLS the Northstar Valdeze because it leaked a LOT of oil, to the tune of 2-3 qt's a week. Once I had resealed the engine ie: manifold plate, oil pan gasket, rear main and 1/2 case seals, I've added only 1qt in almost 5K miles. I keep a couple qts of oil in the trunk and check it at every fill up (once a week).

edwinjn
01-24-05, 02:06 PM
The information posted is not correct. According to GM, acceptable oil consumption is 1 qt. every 2,000 miles, not 1,000.

There are Technical Service Bulletins on thsi issue, and there has been a lawsuit filed against General Motors regarding this issue, & the higher speed vibration issue. If you want information on the lawsuit, please e-mail edwinjn@att.net.
Please provide your year, make & model of car, along with a brief description of how you've tried to rectify your problem(s) and what the dealer or GM told you to do.

LKappenman
01-24-05, 02:08 PM
I have a 94 Seville that has a oil drip it drips onto the manifold and there is a smell. Sometime a little smoke is coming under the hood. It doesn use much oil but the problem is annoying none the less. What should we check first. It was weird that it seems to have started after we took it through a car wash in Southern Cal. (I know we never take it through a car wash) But we were on vacation. It seems to have started after that there is also a kind of whine when we are driving that was at the same time.

kazman
01-24-05, 03:53 PM
I bought my '96 Eldo with 45k on it, now have 161k. At about 95k I rear ended a Ford E350 van on the expressway and ran the thing for about 2 miles with NO coolant (as it had all leaked out, what with the hole through the radiator) to get it off the expressway. When I told the guys at the dealership, they didn't bat an eye, just said they would change the oil and filter. Almost totaled the car, set off both air-bags, and had my local Caddy dealer rebuild it - about $13,500 worth. Ever since I have had it, it goes through about a quart every 1000-1500 miles. I drive pretty hard around town, and hold it at about 77 mph on the highway. A few drops show up on the garage floor over time, so it doesn't leak, and I haven't notice blue smoke from the exhaust at any time. I had decided to chaulk it up to the fact that it has so many more moving parts (you know, 32 valve stems and guides in particular) than any other engine I've owned that it simply "uses" more than I'm used to with other small block GM and Dodge engines. Add my "more moving parts" theory to the cylinder wall cross hatch idea, and there goes the quart of oil. I did change to Valvoline Maxlife around 100k. Still lose the oil, but get about 2-4 more mpg on average than I did with regular Valvoline. By the way, I SWEAR by airbags since my accident.

macx
01-24-05, 04:25 PM
My 97 with 140k just plain leaks. I do just about all my own work, even changed
the steering rack - what a job!!

It's clearly leaking around the pan to block area, and the car smells like
burned oil anytime it's been warmed up. Embarrassing.

We bought the car at 72k. It always took about a quart to a week of mixed driving short trips, just a couple hundred miles. On longer trips, it was more what one expect
normal consumption to be, quite a few hundred miles for maybe 1/2 quart. Seems the warm up / cool down is what causes the most leakage, I suppose with the expansion and contraction of the aluminum.

Out of frustration, and after reading about what a job it is to fix and how much it costs if you take it to a dealer or shop, I put a socket on the bolts I could access
and tightned them a very small amount - just beyond what it took to break them
loose, probably less than 10 degrees of rotation. I was trying very hard to avoid
stripping any threads. Although I am fully capable of going thru the procedure
to do the fix, I just don't have the time to tackle it.

That immediately cut the normal leakage by at about 2/3rd, although it still
smells like burned oil all the time when it's warm. Now I add usually less than
a half quart each week. I'll have to live with that till I get an extended weekend
in warm weather and just get fed up enough with it to tear into it.

It sure seems that, for a brand that purports itself to be a premium car, it
would have incorporated or engineered a production fix for that problem within a
reasonable time, like certainly after a couple years, after it became evident
that so many people were having those problems. It sure hasn't made a good
impression on this owner!

In fact, with all the expensive mechanical components that have failed in the last 30k, I'd have to really see a convincing amount of hard evidence that their quality has improved before buying another Cadillac.

Noodles
01-24-05, 07:49 PM
It is a simple matter of cooling and get up and go. My 1968 427/437 Corvette used a quart of oil about every 800 miles. It needed to do that to lubricate and cool what was going on under my foot. My Dino did the same thing and it was very much a performance engine. The Northstar WILL use oil and spit it out the tail pipe just to keep things cool, calm and collected. If it is not using oil you have a serious problem. In short: Don't worry about it. MY Dino held eight quarts just like the Northstar and both love a heavy right foot. Enjoy, and carry a quart in the boot.

hungryhippo
01-24-05, 10:01 PM
there is nothing good about burning oil. it does not keep things cool. it leaves residue when it is burned. it increases deposits on the pistons where hot spots occur. it does not have octane and makes your car more prone to detonation. it screws up your sensors and cats. air and gasoline are good, not oil

ellives
01-24-05, 10:41 PM
there is nothing good about burning oil. it does not keep things cool. it leaves residue when it is burned. it increases deposits on the pistons where hot spots occur. it does not have octane and makes your car more prone to detonation. it screws up your sensors and cats. air and gasoline are good, not oil

Sigh -- YASAE (yet another self-appointed expert)

Read and learn my young Jedi.

MEJIA
01-24-05, 10:59 PM
This is just a quick question, and perhaps stupid, but I want to know this issue before I make a purchase decision.....

Is the Northstar engine in the new STS 05 also affected with this "missing oil" issue??

Thanks in advance for your help,

And sorry If I kinda got off topic,

Mejia

powerglide
01-24-05, 11:21 PM
my 98 deville has about 90k miles on it, 1 quart per 1500 miles 'dissaper'. Usually dont see any oil under the car except this one time i parked it for a month and saw a couple of drops. I just spend the $2 between every oil change. thats that.
btw i dont gun the thing or drive it hard around town, but i do cruise around 80-90 regularly.

Anthony Cipriano
01-24-05, 11:34 PM
This is just a quick question, and perhaps stupid, but I want to know this issue before I make a purchase decision.....

Is the Northstar engine in the new STS 05 also affected with this "missing oil" issue??

Thanks in advance for your help,

And sorry If I kinda got off topic,

Mejia


There shouldn't be any excessive oil consumption in the rear wheel drive Northstar engines nor the FWD versions beginning with the 2004 model year. There were several design changes made to the piston, ring pack, cylinder honing pattern and valve guide, valve seal, valve spring seat interface. The ring tension is increased significantly to "dry up" the oil consumption issue as well as the design of the rings has been changed for more aggressive oil control.

The 2005 Northstar I'm driving and has been run pretty hard for the last 8000 miles and has used about 1/2 quart of oil.

keysnatch
01-24-05, 11:47 PM
Quite true with the engine oil problem. I have a 1999 Seville STS. Had an oil change in November. Today it's reading 83% engine oil life. The transmission is still holding at 100%. I was told also, that in the summer time to check the oil often because using the AC unit requires more oil usage. Keysnatch

Anthony Cipriano
01-24-05, 11:55 PM
Quite true with the engine oil problem. I have a 1999 Seville STS. Had an oil change in November. Today it's reading 83% engine oil life. The transmission is still holding at 100%. I was told also, that in the summer time to check the oil often because using the AC unit requires more oil usage. Keysnatch


What do you consider a "problem" with what you mentioned? How many miles since the oil change in November? And was the oil life monitor reset when the oil was changed? Unless the transmission is overheated or used for heavy duty towing or something to drive the temperature up for extended periods, the oil life will remain at 100%. Running the AC doesn't "require more oil usage". I don't know who told you that but it doesn't have a shred of truth to it. Summer time oil consumption can be a little worse due to the fact that the oil runs at a little higher temperature (due to the higher ambient temperatures) so it's a little thinner in viscosity and a little more will get past the rings as a result. Nothing to do with the A/C. It's just the hot weather's affect on the oil temperature.

keysnatch
01-25-05, 12:30 AM
I'm really glad you asked the question. In March I will have had the car for two years. This is the second oil change. The readout was showing 18% oil life. I was told to change the oil every 3000 miles. The car had 62K miles when I bought it. It now has 79211 miles. The therm needle never goes past the middle mark or show any signs of overheating. My miles are all city miles. I'm not a traveler. So, now you have me worried.

Keysnatch

Anthony Cipriano
01-25-05, 01:29 AM
I'm really glad you asked the question. In March I will have had the car for two years. This is the second oil change. The readout was showing 18% oil life. I was told to change the oil every 3000 miles. The car had 62K miles when I bought it. It now has 79211 miles. The therm needle never goes past the middle mark or show any signs of overheating. My miles are all city miles. I'm not a traveler. So, now you have me worried.

Keysnatch


I'm not sure why you're worried or what you're worried about. Are you following the oil life monitor for your oil change intervals? If not, then you should. Especially in city driving it will monitor all the driving conditions and predict the oil change interval very accurately for you. 3000 miles may not be soon enough in short trip city driving in the winter. The oil life monitor may predict sooner oil change intervals.

The oil life monitor is absolutely the most accurate way to determine when to change your oil. Just don't go over a year. One year or zero on the oil life monitor, whichever comes first.

Was the oil life monitor reset when the oil was changed last time? You didn't say. The oil life monitor can't tell when you change the oil so you have to reset it when the oil is changed. From that point on it'll monitor all the functions that age the oil and mandate a change and predict the oil life accurately.

If you drive only long trips in the summer time the oil change interval might be as long as 10,000 on your car. On the other hand, with city driving in winter time the oil change interval might be 2500 to 3000 miles easily.

There's a lot of safety factor built into the oil life monitor so there's no concern over running the oil life monitor to zero before changing it.

Even though you drive in the city all the time it would be good to get the car on the expressway once a week and do a few WOT accelerations merging into traffic to wind the engine up, clean the carbon out of the combustion chambers and exercise the rings. The Northstar likes this sort of thing...

cmgrafmc
01-25-05, 03:45 AM
My 2000 DTS warned me 6 months ago, "Check coolant level." I took it in to the dealership, under warranty, and they said "No problem that we could find." They reset the sensor and sent me on my merry way. On the drive home the warning appeared again. I waited some time and then noticed a sqeaking and tapping sound from the engine after starting the engine on cold days...it would become nearly silent after warming up but never really went away. Unfortunately by that time the warranty had expired. I took it back to the dealership and dealt with a new tech who found that not ONLY had the waterpump cover (or housing?) cracked but that the noise was due to "piston slap." The water pump had to be replaced at a cost of $402 and some change. (Now, had they discovered this the first time, it would have cost me nothing.) The tech went on to explain that the fix to this piston slap business was to replace all 8 pistons, rings, etc. That would cost $3200.00

She was, however, able to make GM pay for the piston replacement, labor, etc. This is a car with 19,000 miles on it. For it to need a new water pump so soon was astonishing. The point to all this, however, is that while talking with the tech she told me, directly, that I should notice a big improvement in oil consumption. This wasn't ever an issue as we always changed the oil every 3,000 miles and don't drive it hard, but for her to say that to me was refreshing and honest. She went on to explain that she'd had to order piston replacements for many Northstar engines and was bullish about forcing GM to pay for them. I was very pleased in her ability to correct the situation at a reasonable price (considering the alternative). I'm unclear as to how many Northstar engines face similar problems but I thought it was worth mentioning.

ellives
01-25-05, 05:20 PM
My 2000 DTS warned me 6 months ago, "Check coolant level." I took it in to the dealership, under warranty, and they said "No problem that we could find." They reset the sensor and sent me on my merry way. On the drive home the warning appeared again. I waited some time and then noticed a sqeaking and tapping sound from the engine after starting the engine on cold days...it would become nearly silent after warming up but never really went away. Unfortunately by that time the warranty had expired. I took it back to the dealership and dealt with a new tech who found that not ONLY had the waterpump cover (or housing?) cracked but that the noise was due to "piston slap." The water pump had to be replaced at a cost of $402 and some change. (Now, had they discovered this the first time, it would have cost me nothing.) The tech went on to explain that the fix to this piston slap business was to replace all 8 pistons, rings, etc. That would cost $3200.00

She was, however, able to make GM pay for the piston replacement, labor, etc. This is a car with 19,000 miles on it. For it to need a new water pump so soon was astonishing. The point to all this, however, is that while talking with the tech she told me, directly, that I should notice a big improvement in oil consumption. This wasn't ever an issue as we always changed the oil every 3,000 miles and don't drive it hard, but for her to say that to me was refreshing and honest. She went on to explain that she'd had to order piston replacements for many Northstar engines and was bullish about forcing GM to pay for them. I was very pleased in her ability to correct the situation at a reasonable price (considering the alternative). I'm unclear as to how many Northstar engines face similar problems but I thought it was worth mentioning.

Well duh... of course she's eager to "force" GM to pay for parts.... it means she gets the parts for free PLUS gets to charge you labor rates to do the work. I'm going to guess Anthony Cipriano will have something to say about their "diagnosis" of piston slap on a car with 19K miles on it -- ridiculous.

Oh and by the way, they should have covered the cost of the water pump housing too... even though the warranty had expired, you originally complained of the problem prior to the expiration so it should be covered. It's not your fault they misdiagnosed (non-diagnosed) the problem.

I'd be willing to bet a more aggressive driving style would solve the "piston slap" issue (WOT a few times a week.)

Anthony Cipriano
01-26-05, 12:35 AM
Yes, there are a lot of "piston replacements" as it's a large warranty job. Most of them are unjustified, but...

I was a bit surprised at the $400 for the water pump cover crack. The cover being cracked or seeping is about the only reasonable solution to the coolant leak and fix as you describe. The water pump cover is readily visible just behind the radiator. It's incredibly easy to replace. I'm not sure of the part cost (if it needed replacing after all) but the labor is well less than an hour to R&R it - which doesn't add up to $400.00. The water pump cover is a diecast aluminum part which is pretty robust so how it would "crack" is surprising at those mileages. Besides, if you reported the problem while it was under warranty and can document that it should be a warranty item.

cart69
01-26-05, 01:28 PM
when i bought my 94 sls it had 72k on it that was a little over a year ago, and when i got it before its first oil change its used about 3 quarts, thats within approx 3k miles, that made me a little leary of the car, then i came here and read about runnin it heard every now and then and that makes sense so i tried it, and enjoyed it and do it at least once a week now and my oil consumption problems have almost gone away, between oil changes since then it might use a quart total usually not even that much, and the car has 87k on it now so its had a few oil changes, so i am a firm believer in the run it hard cure for the oil consumption issues since it greatly helped mine.

But thanks to this website i found that info, info instead of paying the dealer to do something or rebuilding the engine myself. Thanks to all of you on here!

ellives
01-27-05, 07:59 AM
My 2000 DTS warned me 6 months ago, "Check coolant level." I took it in to the dealership, under warranty, and they said "No problem that we could find." They reset the sensor and sent me on my merry way. On the drive home the warning appeared again. I waited some time and then noticed a sqeaking and tapping sound from the engine after starting the engine on cold days...it would become nearly silent after warming up but never really went away. Unfortunately by that time the warranty had expired. I took it back to the dealership and dealt with a new tech who found that not ONLY had the waterpump cover (or housing?) cracked but that the noise was due to "piston slap." The water pump had to be replaced at a cost of $402 and some change. (Now, had they discovered this the first time, it would have cost me nothing.) The tech went on to explain that the fix to this piston slap business was to replace all 8 pistons, rings, etc. That would cost $3200.00

She was, however, able to make GM pay for the piston replacement, labor, etc. This is a car with 19,000 miles on it. For it to need a new water pump so soon was astonishing. The point to all this, however, is that while talking with the tech she told me, directly, that I should notice a big improvement in oil consumption. This wasn't ever an issue as we always changed the oil every 3,000 miles and don't drive it hard, but for her to say that to me was refreshing and honest. She went on to explain that she'd had to order piston replacements for many Northstar engines and was bullish about forcing GM to pay for them. I was very pleased in her ability to correct the situation at a reasonable price (considering the alternative). I'm unclear as to how many Northstar engines face similar problems but I thought it was worth mentioning.

HOw about posting the name of the dealer ? Inquiring minds want to know.

NewCaddyFan
01-28-05, 05:30 PM
I'm not sure why you are worried or what you're worried about.

Are you following the oil life monitor for your oil change intervals? If not, then you should.


What about the first few thousand miles on a new NSv8 in my SRX?

Thanks

Anthony Cipriano
01-28-05, 11:49 PM
I'm not sure why you are worried or what you're worried about.

Are you following the oil life monitor for your oil change intervals? If not, then you should.


What about the first few thousand miles on a new NSv8 in my SRX?

Thanks


There's no problem following the oil life monitor for the first oil change. The factory assembly lube boosts the antiwear additives in the first oil file which would be the thing depleted a little quicker during breakin so that first crankcase full of oil will easily handle what breakin is required and last through the first oil life on the monitor.

OneArmedBandit
01-30-05, 12:11 PM
Okay, I know i'm getting in on this one kinda late, but I thought you might want to see the GM Service Bulletin related to this topic. I work as a Service Consultant in a Buick, Cadillac, Nissan garage and i am faced with this topic ALL the time. You might find this interesting reading.

Document ID# 1358091
1998 Cadillac Seville
Information on Engine Oil Consumption Guidelines #01-06-01-011A - (Jul 22, 2003)
Information on Engine Oil Consumption Guidelines

All 1996-2004 Passenger Cars and Gasoline Powered Light Duty Trucks Under 8500 LB GVW

except Chevrolet Corvette

This bulletin is being revised to update the Model Years. Please discard Corporate Bulletin Number 01-06-01-011 (Section 6 -- Engine).

All engines require oil to lubricate and protect the load bearing and internal moving parts from wear including cylinder walls, pistons and piston rings. When a piston moves down its cylinder, a thin film of oil is left on the cylinder wall. During the power stroke, part of this oil layer is consumed in the combustion process. As a result, varying rates of oil consumption are accepted as normal in all engines.
Oil Consumption

The accepted rate of oil consumption for engines used in the vehicles referenced is 0.946 liter (1 qt) in 3200 km (2000 mi). This rate only applies to personal use vehicles, under warranty, maintained in accordance with the appropriate maintenance schedule, with less than 58,000 km (36,000 mi), or 80,450 km (50,000 mi) for Cadillac, driven at legal speeds in an unloaded (for trucks) condition.

Many factors can affect an owner's concern with oil consumption. Driving habits and vehicle maintenance vary from owner to owner. Thoroughly evaluate each case before deciding whether the vehicle in question has abnormal engine oil consumption.
Gasket and External Leaks

Inspect the oil pan and engine covers for leakage due to over-tightened, damaged, or out of place gaskets. Inspect oil lines and fittings for signs of leakage.
Improper Reading of the Oil Level Indicator (Dipstick)

Verify that the dipstick tube is fully seated in the block. When checking the oil level, make sure the dipstick is wiped clean before taking an oil level reading and fully depress the dipstick until the shoulder bottoms out on the dipstick tube. The dipstick should be the proper part number for the engine/vehicle that is being checked.
Not Waiting Long Enough After Running Engine to Check Oil Level

The vehicle should be allowed to sit for at least 5 minutes (20 minutes for the 3.4 L LQ1), after the engine has been shut off, before taking an oil level reading to assure the oil has had enough time to drain back into the crankcase. In order to ensure accurate results, the temperature of the oil should be close to the same temperature as the last time the oil level was checked.
Improper Oil Fill After an Oil Change

Following an oil change, verify that the proper amount and type of oil was put in the engine and that the oil level on the dipstick is not above the full mark or below the add marks. Refer to the Owner's Manual or Service Manual for information on recommended oil quantity, viscosity, and quality.
High Speed or High RPM Driving

Continuous driving at high speeds/high RPMs may increase oil consumption. Because this may not always be an everyday occurrence, it is hard to determine exactly how much the oil economy will be affected.
Towing or Heavy Usage

Towing a trailer will increase oil consumption and may cause oil consumption to fall below the normal accepted rate referenced in this bulletin for an unloaded vehicle in a personal use application. Large frontal area trailers will further increase the work required from the engine, especially at highway speeds, and thus increases the rate of oil consumption.
Crankcase Ventilation System

Verify that the positive crankcase ventilation (PCV) system is operating properly. Incorrect PCV valves, blockages, restrictions, or damage to the PCV system can result in increased oil use.
Oil Dilution (Fuel and Water)

On vehicles that are usually driven short distances, less than 8 km (5 mi), especially in colder weather, unburned fuel and condensation generated from cold engine operation may not get hot enough to evaporate out of the oil. When this occurs, the dipstick may indicate that the oil level is over-full. Subsequent driving on a trip of sufficient length to enable normal engine operating temperature for 30 minutes or more, in order to vaporize excess moisture and fuel, may give the customer the impression of excessive oil consumption.
Engine Temperature

If an engine is run at overheated temperatures (see Owner's Manual or Service Manual) for more than brief periods, oil will oxidize at a faster than normal rate. In addition, gaskets may distort, piston rings may stick, and excessive wear may result. Verify that all cooling system components are in proper working order.
Engine Wear

Piston scuffing, excessive piston-to-wall clearance, tapered or out of round cylinders, worn, damaged or improperly installed valve guides, seals and piston rings will all cause an increase in oil consumption.
Measurement of Oil Consumption

Engines require a period of time to BREAK IN so that moving parts are properly seated. Therefore, oil economy should not be tested until the vehicle has accumulated at least 6400 km (4000 mi). An exception would be allowed only if an engine is reported to be using more than 0.946 liter (1 qt) in 1600 km (1000 mi).

1. Verify that the engine has no external leaks. Repair as necessary.
2. Verify that the engine is at normal operating temperature (see Owner's Manual or Service Manual).
3. Park the vehicle on a level surface.
4. Wait at least 5 minutes (20 minutes for the 3.4 L LQ1), after the engine is shut off, before checking the oil level to make sure that most of the oil has had time to drain back into the crankcase.
5. Verify that the oil level is at, but not above, the full mark on the dipstick, and that the proper viscosity and quality oil are being used as recommended in the Owner's Manual.
6. Record the vehicle mileage, date, and exact oil level on the form included in this bulletin.
7. Ask the customer to verify the oil level, each time the vehicle is fueled, following steps 1-6 and return the vehicle to the dealership if the oil level is found at or below the add mark, 0.946 liter (1 qt) low. If the oil level remains above the add mark, the customer should continue to operate the vehicle and verify the engine oil level until 3200 km (2000 mi) has accumulated before returning to the dealership for a final evaluation.
8. If the final evaluation shows that the engine uses more than 0.946 liter (1 qt) in 3200 km (2000 mi), follow the published symptom diagnostics as described in the appropriate Service Manual. If the oil consumption test shows that the engine uses less than 0.946 liter (1 qt) in 3200 km (2000 mi), explain to the customer that their engine meets the guidelines for oil consumption.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

Copyright General Motors Corporation. All Rights Reserved.

maxnix
02-01-05, 12:16 PM
Engine Wear

Piston scuffing, excessive piston-to-wall clearance, tapered or out of round cylinders, worn, damaged or improperly installed valve guides, seals and piston rings will all cause an increase in oil consumption.
Interestingly, the bulletin doesn't address resolution of these problems.

Inspector
02-01-05, 05:35 PM
I own a 94 Concourse Deville. It has over 152K on the clock and will use less than a qt of oil in 4500 miles which is my usual change milage. The only problem that I have with this car is the road sensing struts and the electronic ride control. Other than those items I like driving this car. Just think how I will like it after the struts are changed and the ELC exhaust valve is addressed.

Anthony: I still haven't gotten your Email. Try me again at brad1454@msn.com

Denny

Debiz
02-06-05, 06:53 PM
Bought my 98 Deville from a friend last June w/ 97000+ miles. He told me about the oil usage and how a quart is need every 1500 miles, but I found myself using ALOT more, nearly 4 quarts between oil changes. No leaks, no burning...now have 104,000+ miles and switched "high-mileage" oil at about 102,000 -- so far have not had to add any oil at all. If you have high mileage, give it a shot.

--- DM

dwight.j.carter
02-10-05, 05:03 AM
I recently purchased a 99 STS and I had the car inspected before I bought it and they found an oil leak leaving a 50 cent piece size oil spill on the ground however the car sat in the lot for a long time is it possible since I started driving it for the leak to go away because it dosn't seem to be leaking anywhere the mechanic also said that it was blowing onto the manifold but I smell no oil and even if it was blowing back the oil would hit the ground when I am not moving well anyway I got the dealer to lower the price when the leak was found and it dosn't seem to be bad at all.:cool:

roebigd
02-10-05, 10:55 AM
Recheck The Belt For The Waterpump , This Belt If Slightly Loose Will Cause Intermittent Overheating, The Problem We Are Fixing The Most Of Now When They Start Overheating And Losing Coolant Is The Head Bolts Pulling The Threads Out Of The Block, If That Happens The Entire Engine Has To Be Removed And Heads Taken Off And We Redrill The Block And Install Special Stainless Steel Inserts And New Head B0lts.

Terry Adams
02-10-05, 12:49 PM
GM has a supposed fix for some years of Northstar that involves cleaning the cylinders and piston rings. You squirt a special cleaner into the bores through the spark plug holes, then let the car sit for two hours for the cleaner to soak in between the rings, then vacuum the leftover cleaner out. Then you change the oil (without the filter), drive the car for 20 minutes, then change the oil *and* filter since the oil will now have the gunk from the cylinders. This is a job for a dealer, since the vacuum is a special tool designed just for this job.

DON'T WASTE YOUR MONEY WITH THIS FIX. IT DOES NOT WORK. MY 98 STS w/ 92,000 MILES ON IT USES APPROXIMATLY 1 QT PER 1000 MILES. IT HAS DONE THIS FROM THE TIME I PURCHASED IT 2-1/2 YEARS AGO WHEN IT HAD 57,000 MILES ON IT. I LOOKED TO THE DEALER FOR SOME ANSWERS AND WAS SOLD THAT BILL OF GOODS. THE CAR WAS NOT UNDER WARRENTY SO I PAID ABOUT $800.00 TO HAVE THE CYLINDERS CLEANED. THIS WAS AT ABOUT 67,000 MILES. IT MADE NO DIFFERENCE EXCEPT I COULD HAVE BOUGHT A HELL OF A LOT OF OIL FOR THE $800.00. THE CAR HAS ALWAYS RUN PERFECT AND STILL DOES. A FRIEND OF MINE HAD A 98 STS w/ 165,000 MILES ON IT AND HE SAID IT USED A QUART PER 1,000 MILES ALMOST FROM DAY ONE. IF IT USES OIL THATS THE WAY IT IS GOING TO BE UNTIL THE MOTOR IS TORN DOWN AND THE CLEARANCES ARE TIGHTENED UP

TERRY

Spyder
02-10-05, 03:52 PM
We've got another one! :cookoo:

DBLDN11
02-10-05, 06:14 PM
AHHHHHHH!!!

Lots of folks making costly repairs that are unecessary! This engine will drink oil - that needs to be accepted upon purchase of a used Caddy.


I'm new here, but this works for me. Drive your Northstar hard at least once a week. Get out and hammer it (within legal limits of course!). These babies were designed to be run, so oblige them.

Accept the fact that you will be adding at least one quart of oil between changes (many will have to add a little more than 1.5 quarts). Stop fighting it. This machine uses oil. It holds 7.5 quarts, and an additional one or two quarts every 3000 miles amounts to less than $5. As long as you have no smoke and the car runs strong...you have no reason to worry. Sure, many of us are used to driving Toyota Corollas with puny little 4cyl's that don't use a drop of oil (or gas!)...but you're not in that game anymore. Keep your car clean and well maintained, and enjoy your day. The endless stress about the usage of $5 worth of oil every month is doing you much more harm than the actual burnoff is doing the engine.

My current 98 STS has 93K on the clock, it uses 1qt every 1500 miles or so...and it runs like a champ. I've moved on. I don't worry about it. Meanwhile, my uncle's 98 Eldo with 70K uses the same amount and he's constantly freaking out about it and complaining to anyone who will listen. Nothing negative is going on, his car starts right up and runs strong with no smoke...and he's not getting any enjoyment out of it, but that's his fault...not the car.

For reference purposes: my previous "big" car (just sold) was a 2000 Mercedes S430. This big tank had an old-school V8 that held 10qts of oil. I had 67K on the clock...and it used 2qts every 3000 miles (often reminding me to "Please add 1.0 Litres of oil at nearest service station"). Normal. Under extended warranty, it was in the shop every now and then for various electronic nonsense, and every single S I came across used oil. The very friendly techs at WorldWide Motors (Mercedes) spent time nearly every day explaining that these big cars used oil - all within normal operating conditions.
The car got 16mpg, used oil, and I enjoyed every minute of it.

shookman34
02-11-05, 07:15 PM
I'm just curious if anyone knows if it is still ok to go by the oil life indicator on higher mileage cars...I have a '97 STS with 118,000 miles. Not a ton of miles yet, but just wondering if it becomes necessary to change the oil sooner as the engine gets more worn out. I generally go by the 3000 miles rule for changing the oil, but going by the oil life indicator...I could go twice as long.

cl1986
03-06-05, 11:47 PM
DON'T BUY A NORTHSTAR! NOT ONLY DO THEY USE OIL " A QUART PER THOUSAND MILES". That's what they told me was normal too.....That is BS!. To me that means somehthing is wrong in the design.....Do yourself a favor, check the threads on not only the oil consumption but the overheating of the Northstar.....Get yourself an owner's manual for a Northstar engine...it states how the Northstar knows how to automatically shut down half the engine when overheating and go into "limp along mode". Why would they put that in the design of a vehicle? Answer is: they didn't. The northstar not only burns oil, it overheats and in both instances GM tries to tell you it's designed that way....Well, if I am paying 45k+ for a car, it better not burn oil or overheat....I dumped both of my caddy's (Sedan De Ville and Eldorado) and bought a Lexus and a Honda. Have never been happier!!!!!!Screw Cadillac...buncha liars.... Don't take my word for it....search the threads and google and listen to all the others having the same issues...

What a fing idiot. A lexus and a honda. Talk about crap. Neither have any power and i dont care what model u have. Hahahha, im still laughing. THis is the funniest thing ever!!! Oh no, 100 people out of a million are having problems, hahha. WHat an idiot. By the way, the hondas are always in the shops, dont even have time for my caddies oil change, they have to put the hondas back together. My eldo will outlast any honda out there and get better milage and have more power. ROFL!! Bring your ricer over so i can stomp your ass.

cl1986
03-06-05, 11:50 PM
DON'T WASTE YOUR MONEY WITH THIS FIX. IT DOES NOT WORK. MY 98 STS w/ 92,000 MILES ON IT USES APPROXIMATLY 1 QT PER 1000 MILES. IT HAS DONE THIS FROM THE TIME I PURCHASED IT 2-1/2 YEARS AGO WHEN IT HAD 57,000 MILES ON IT. I LOOKED TO THE DEALER FOR SOME ANSWERS AND WAS SOLD THAT BILL OF GOODS. THE CAR WAS NOT UNDER WARRENTY SO I PAID ABOUT $800.00 TO HAVE THE CYLINDERS CLEANED. THIS WAS AT ABOUT 67,000 MILES. IT MADE NO DIFFERENCE EXCEPT I COULD HAVE BOUGHT A HELL OF A LOT OF OIL FOR THE $800.00. THE CAR HAS ALWAYS RUN PERFECT AND STILL DOES. A FRIEND OF MINE HAD A 98 STS w/ 165,000 MILES ON IT AND HE SAID IT USED A QUART PER 1,000 MILES ALMOST FROM DAY ONE. IF IT USES OIL THATS THE WAY IT IS GOING TO BE UNTIL THE MOTOR IS TORN DOWN AND THE CLEARANCES ARE TIGHTENED UP TERRY


What the hell, it doesnt cost that much to put it in second gear and wind it up to 70 mph and let it back down to 30 and reapeat 12 times. I think the most it would cost is around $2 for the gas u use. How else would u clean out the engine

Anthony Cipriano
03-07-05, 12:05 AM
I'm just curious if anyone knows if it is still ok to go by the oil life indicator on higher mileage cars...I have a '97 STS with 118,000 miles. Not a ton of miles yet, but just wondering if it becomes necessary to change the oil sooner as the engine gets more worn out. I generally go by the 3000 miles rule for changing the oil, but going by the oil life indicator...I could go twice as long.


You can continue to use the oil life monitor. The oil life doesn't change dramatically due to mileage on the engine and there's plenty of "reserve" in the oil life monitor calculations to take that into account.

Ron Natali
03-31-05, 12:39 PM
I have a '97 STS (58K miles)and so does my son (82K miles). Between the two of us, we have oil consumption, had oil leaks due to the crankcase leaking at the "split half" area, and overheating problems. The oil consumption is a given as you will note in all comments on the NS engine. The oil leak was a result of the crank case leaking. The dealer pulled the pan and resealed the surfaces. The over heating problem was a condition where the head bolts pull/stretch the threads in the aluminum block. The dealer installed steel inserts and put the engine back togetehr - did not have to shave the heads. The NS has good features and is a good performer but GM needs to correct their problems and not relay on warranty work and inconvenience to their customers.

PSO
04-01-05, 11:20 PM
Oil question can I use 20-50 wt oil in a 99 SLS will it cause problems being thicker? Question two, is it better to get original catalytic converter or an after market one. Anyone have answer?

Anthony Cipriano
04-02-05, 12:19 AM
Oil question can I use 20-50 wt oil in a 99 SLS will it cause problems being thicker? Question two, is it better to get original catalytic converter or an after market one. Anyone have answer?


There's really no reason to run an oil that thick in that engine. It'll cause very high oil pressure on cold starts even in warm ambients. I'd recommend the factory spec'd 10W30 viscosity or a 15W40 at the most in very hot climates.

Cnjmale
04-21-05, 02:25 PM
Hello all i have a 2000 white diamond deville has about 140,000ml now i got it when it had 50,000mls and ever since i had it i drive it 5days a week all highway average of 70 to 75 mph and i use a qt of oil every 1,000ml like clock work and no oil drips at all on my garage floor.



Pete, NJ

1996deVille
04-22-05, 08:50 PM
Same in my case. WOT and all - makes no difference.

signengraver
06-17-05, 02:09 PM
Last winter i was driving 1999 seville sls up virginia mtns. and experienced oil smell from leak on manifold. Nice 75000 miles only. my 84 corvette did same thing. whats up, Dealer says lower case leak 1800.00 to fix. i see no oil on ground at home florida and no smell. i guess the pressure in mtns caused more leak and dripping back on manifold going up hills. very annoying especially when cadillac say do not fix or could cause other problems. too bad car is fun in mtns.

malcolm
06-17-05, 02:53 PM
Knock wood after about 3500 miles my 05 STS V8 has not used any yet.

Fossilswatchguy
07-06-05, 09:32 PM
My cadillac leaks oil worse when it is on a hill with the front of the car pointing down. Has anyone had a problem with this??? I just bought my car, I have a 94 Concours, bought it from and an older couple. Is this anything to be worried about??? If so what needs to be done to stop the leak???? When it's on the hill, it's more than a few drops.

powerglide
07-06-05, 09:38 PM
Welcome to the forums Fossil.....there's lots of knowledgeable folks in here.

Can you tell where the leak is coming from?

If you do a search on the forum about oil leak and pan bolt, there's info on here about how to go about checking if theres a leak coming through your bolts. (I think you pull one at a time, inspect, clean, apply sealant etc)

someone will jump in and offer you advice soon....good luck

Fossilswatchguy
07-06-05, 10:17 PM
The bolts where??? I don't work on cars... so I do have a friend that does and it would help me tell him if you could tell me where the bolts are... I hope that we can rectify this instead of it costing me thousands. I'd hate to spend more to fix it than i paid for it. LOL. :crying:

cl1986
07-06-05, 10:52 PM
On the oil pan where the oil plug is!!

Fossilswatchguy
07-07-05, 06:52 PM
Has anyone else been able to fix their problem with the oil pan screws solution?

dkozloski
07-07-05, 07:47 PM
Evidently the situation no longer exists. My '04 CTS VVT 3.6L V6 takes 11,000 miles to time out the oil life system and the level never changes.

powerglide
07-07-05, 08:28 PM
Evidently the situation no longer exists. My '04 CTS VVT 3.6L V6 takes 11,000 miles to time out the oil life system and the level never changes.


I think this was mainly a Northstar issue, and yes I believe it still exists.....dunno about your 3.6.....sounds like a solid motor

powerglide
07-07-05, 08:30 PM
Has anyone else been able to fix their problem with the oil pan screws solution?

yes there are accounts (in this Northstar Section) of folks who fixed a leak this way [thats where I got it from]....try a search on here and you'll see more detailed accounts


But to be honest....if your leak is that severe then it might not be the bolts (the leak though the bolts are a pretty slow process I reckon)

Get under there, make sure everything is tight (drain bolt, filter etc) see if you can spot the leak. If not, claen up all the leaked oil really well, then park, the get under there and see if you spot it now.

If all else fails there is a process called the dye test where the put some dye in your oil so you can see the leak more clearly....I priced the job at around $65 which is probably WAY high as I assume the job probably consits of dropping some dye in the oil (maybe an oil change).