: Northstar Oil Usage



Buddy94
02-16-04, 12:43 AM
Hey,
I am looking for some information on the oil usage of the northstar engine. I am looking at a 2000 STS. If I purchase it, it will be my second Caddy. I have heard that the northstar engine requires a quart of oil every 1400 miles. For the past six years, I have driven my 94 Caddy with the 4.9L from Arizona to Florida with no loss of oil. Does anyone out there have a northstar engine? If so, can you share some information on this topic?

Buddy94

Anthony Cipriano
02-16-04, 11:36 AM
Hey,
I am looking for some information on the oil usage of the northstar engine. I am looking at a 2000 STS. If I purchase it, it will be my second Caddy. I have heard that the northstar engine requires a quart of oil every 1400 miles. For the past six years, I have driven my 94 Caddy with the 4.9L from Arizona to Florida with no loss of oil. Does anyone out there have a northstar engine? If so, can you share some information on this topic?

Buddy94

There has been a lot discussed on Northstar oil consumption. Search in the archives for more info. It's not unusual for a Northstar to use more oil than some other engines. It's a high performance engine and has to allow a little more oil to the top rings for lubrication as as well as down the 32 valve guides.

Design intent for oil consumption would put the engine at about 4000 miles per quart consumption but due to the variables in production parameters there are engines that will use 1 quart per 1000-1500 miles - perfectly normal and acceptable - but more oil consumption than "intended". Nothing will be wrong with the engine but the continuous oil adds are aggravating. If this is the case then understand that the engine is probably going to run a long, long time like that as the cylinder walls, rings, valve guides, etcetera like all that oil that you are putting in and the continuous oil adds fortify the used oil in the sump and replenish the additive package in the oil that is slowly depleted under normal usage.

Comparing the 4.9 to the Northstar is an apples to oranges deal. The 4.9 is an excellent engine for it's purpose but does not offer nearly the performance, durability, fuel economy and emission control capability of the Northstar. The Northstar is a high output engine and likes to be "used".

The best way to minimize oil consumption in a Northstar is to keep the sump filled slightly low (many are continuously overfilled) by only checking the oil level when hot and only filling the sump with 7 quarts of oil (7.5 with a dry filter at a change.) A typical 8 quart fill at a change is "required" to put the oil level on the full mark when cold but is actually overfilling the crankcase promoting oil consumption.

Use conventional mineral oil (synthetic is not required at all) as it tends to provide better oil consumption.

And last but not least, air the engine out frequently. It likes to be used and red-line upshifts at wide-open throttle help promote clean combustion chambers, exercise the piston rings to keep them free of carbon buildup and keep them mobile and to ensure the engine is broken in and maximum sealing is obtained. The Northstar does not like to be babied around. It likes to be run hard frequently with a WOT blast in merging or whatever. Even engines reported to use 1 quart per 1500 miles tend to improve to 2500 miles per quart or better when subjected to a regular schedule of use and "abuse".

Anthony Cipriano
02-16-04, 11:42 AM
Hey,
I am looking for some information on the oil usage of the northstar engine. I am looking at a 2000 STS. If I purchase it, it will be my second Caddy. I have heard that the northstar engine requires a quart of oil every 1400 miles. For the past six years, I have driven my 94 Caddy with the 4.9L from Arizona to Florida with no loss of oil. Does anyone out there have a northstar engine? If so, can you share some information on this topic?

Buddy94

Buddy. This is a copy/paste of a message posted some time ago. I hope it helps...

The subject of oil consumption really does not have a "final" answer. The fact is that there is some variability in oil consumption in all production engines. Regardless of who makes them on which continent. All the manufacturers recognize this and virtually all of them will call oil consumption as great as 1 quart in 1000 miles "normal", "acceptable", "allowable", "within production tolerances" etcetera. This doesn't mean that all engines will get 1000 miles per quart (MPQ) or that the engine was designed to get 1000 MPQ. It just recognizes the fact that there are going to be some engines that get 1000 MPQ that will be perfectly fine upon disassembly and will have nothing "wrong" with them.

The variables that usually enter into oil consumption are primarily associated with the piston/ring/cylinder bore. The number of valves or type of valve actuation has little to do with it.

The single biggest variable and the one that haas been discussed at great length on this forum is the cylinder bore finish or the cylinder honing pattern. The higher perfromance the engine is the more attention must be paid to the honing pattern and retention of oil on the cylinder walls to lubricate the piston and rings at full load, high RPM operation. The Northstar engine uses a very agressive cylinder bore finish that tends to retain a lot of oil to protect the piston and rings. When the blocks are honed at the factory there is a tolerance in the bore finish due to the fact that the honing stones will wear and need replacement. A brand new stone gives a slightly more agressive pattern than a "used" stone. So a block honed with new stones will have a more aggressive finish and most likely will use more oil.

Another variable is bore roundness. Like it or not, the bores tend to "move" slightly as the engine heats up and cools down and bolt tensions relax over time. All this contributes to slight bore out of roundness that is not bad or good - just different.

Carbon buildup in the rings and reing sealing are also variables that come into play with breakin, operating schedule, type of oil used, etcetera.

The one thing that I can attest to is that many, many customer oil consumption complaint engines have been torn down with absolutely nothing wrong found. The engines are often reassembled and put into test cars and driven by the engineers and more often than not the high oil consumption does not repeat itself. The single most common cause seems to be break-in or lack there of. Many, many oil consuming Northstar engines are "fixed" by some full throttle operation. We often joke about "driving it like you stole it" but it really is no joke. The Northstar engine was designed as a high performance engine to be run hard and fast. Those that are run hard typically exhibit excellent ring seal, little carbon build up and good oil economy. We have seen engines with tens of thousands of miles on them that the rings have not sealed or mated to the sides of the ring grooves because the operating schdule was so light duty. The moral here is to flog it often.

In any case, the nice thing about the engines with the more aggressive honing pattern is that the pistons, rings and bores will last forever. It is very common to tear down a 200,000 mile Northstar engine and still see the original honing pattern in the cylinders. There is never any sign of cyilnder wall wear and the idea of a wear "ridge" at the top of the cyilnder bore is something that is laughable on a Northstar.

The other nice thing about a little oil consumption is that it adds tremendous safety factor to the oil change interval. Nothing could be better for the engine than an occasional quart of fresh oil. You can take the worst oil on the market and add a fresh quart every 1000 miles and over the life of the engine the wear will be better than an engine run on the best oil with no adds between changes.

While no one in the engineering commumnity wants high oil consuption the fact is that there is some variability in the oil consumption of an engine manufacturered at the rate of 1200 per day. The specs of what is "normal" simply reflects this - it does not imply that all engines whould get this or that somthing is wrong with and engine that gets more or less oil consumption.

There have been a lot of engineering changes over the years on the Northstar aimed at reducing the overall oil consumption and reducing the variability in the oil consumption of different engines. Many changes have been made to the honeing process to make it moe consistent. Changes to the piston and ring groove treatment have been made to make it more resistent to wear, poundout and microwelding at low oil retention rates. Regardless, there is still some variability.

One other thing that affects oil consuption, or the customers perception of oil consumption, is the move toward longer and longer change intervals. With the allowable change interval reaching as high as 12,500 miles on a 2003 Northstar if the oil life monitor is followed this could mean the addition of 3,4 or 5 quarts of oil to a very healthy engine. If the owner changes their oil every 2000 or 3000 miles, despite the oil life monitor recommendations, then they would not have to add any oil between changes. The oil consumption is the same - the amount added between changes is all that's different. Yet, many customers do not make the distinction. Field surveyrs repeatedly show that "acceptable" oil consumption means "not having to add between changes" - whatever MPQ that is.

The issue of oil consumption is very emotional, too, as many people perceive higher oil consumption as 'poor quality" or an indication that something's wrong. Blue smoke, fouling plugs, noise - those are signs that something's wrong. Using 1 quart in 1000 miles might be perfectly normal for an engine that has the high limit "rough" hone finish and is perfectly in spec. Yet it will be perceived differently.

The Northstar engine in particular was designed to be a high performance engine and to perform well at high speeds and high loads. The engines are tested at loads and speeds for time periods few customers will ever be able to duplicate. It's unfortunate that the engineering that goes into making the engine capable of such running sometimes contributes to more oil consumption - especially as the production machining tolerances are taken into account.

The items mentioned about overfilling also apply. Make sure that the system is not overfilled as any excess oil will be pushed out the PCV. The best bet is to always check the oil hot and keep it midway between the add and full mark. Don't always top off and don't top off cold to the full mark as that will overfill the sump.

I hope this helps rather than adding more fuel to the fire. No pun intended.

Incidentally, there's a lot in our archives. Check using "oil consumption" and read on. Always keep in mind that for every "oil burner" you read about on the internet there are 10,000 or more driving around perfectly fine that the people aren't posting about. You're always going to read about the horror stories on the internet. How many people search Google for a Cadillac forum just to post about how they haven't had a particular issue?

If you had a BMW then you must enjoy the www.my750.com (http://www.my750.com) site. Typical "hate site" that pops up to promote so called "epidemic" problems with a particular product.

Buddy94
02-16-04, 07:42 PM
Thanks for the info. Just returned from Don Mackey Cadillac in Tucson. I spoke with a gentleman who goes by the name of Chuck. He stated that a N* should get about 3000 miles before adding any oil. He went on to say that his customers get their every service done 3000 miles without adding oil between services.

I went to Lawley Cadillac in Sierra Vista and the person there confirmed what this site was saying (1000-1400 MPQ). It was explained that there was nothing wrong with the engine; it was designed to work that way. They took the time to explain a lot more to me. It was not a sales pitch, considering what I received in Tucson. I will, however, keep my 94 Caddy with the 4.9L for now. Thanks for the help and all the info I received.

Buddy94

c_a_s_2
03-01-04, 02:58 AM
What is your opinion on use of SLICK50 in my Northstar? I bought it, but have not added it, yet. Waiting for oil change time. My car is 98 eldo, 40K, no drips, and very low oil consumption, right now. .........I just want this car to Last and Last and Last. cs

Anthony Cipriano
03-01-04, 02:58 PM
What is your opinion on use of SLICK50 in my Northstar? I bought it, but have not added it, yet. Waiting for oil change time. My car is 98 eldo, 40K, no drips, and very low oil consumption, right now. .........I just want this car to Last and Last and Last. cs


Please don't waste your money...

std1
09-18-06, 03:06 PM
I have had 3 Northstar equipped Cadillacs and know about 5 other people who have had them as well. Like clockwork, the heavy oil consumption seems to begin after 40,000 miles. I know an engineer who obtained a Northstar engine from a junkyard and cut it into cross sections. (He said Northstars are widely available due to their not being conducive to rebuilds) This engineer noticed that the cams in the Northstar seem to meet the valve stems at a somewhat acute angle which suggests a side movement pressure to the valves in addition to the expected up and down movement. He stated the valve guides in the engine he examined were worn. The question here is has anyone ever factually demonstrated that valve guide wear is not a factor in the Northstar's prodigious oil consumption?

Prior to the 3 Northstar equipped STS's I have had, I had a '93 with the 4.9 litre engine. I sold to my brother who still has it with an excess of 240,000 miles and it still does not use oil. The 4.9 litre engine was far more enjoyable to drive around town. Its 2 valve per cylinder design provides nice low end torque for everyday driving which is really what most people want most of the time. Load up a Northstar car with people and A/C and the idea of having to thrash and mash the pedal to get it to respond slight speed changes is draining on both my energy as well as the gas tank. The 4.9 only needed only a slight bit more pressure on the accelerator to respond very well. Also, how much $3.00 per gallon gas has to be wasted in order to get the rings to re-seal?

I do not know if I will ever understand the reasoning that went into putting the Northstar into a street car. It is only fun to drive when the pedal is to the metal but how often can one do that. A friend of mine was just visiting with his 740iL. The engine sounds as smooth as a sewing machine and the car does not shake at all. In contrast, the overly complex Northstar design creates a disconcerting sound. Something like a "clanking and clattering cacophony of cams and cogs".

Ranger
09-18-06, 04:22 PM
My Northstar seem to take very little pedal to get it moving and gives back excellent fuel milage. Have you read the Technical Archives at the top left of this page regarding oil consumption?

STS-in-Nottingham
09-18-06, 04:22 PM
In contrast, the overly complex Northstar design creates a disconcerting sound. Something like a "clanking and clattering cacophony of cams and cogs".


I've owned two STS's and neither of them made any clanking or clattering noises.
Both drive beautifully at normal speeds too, silky smooth and whisper quiet.

GailyBedight
09-18-06, 04:30 PM
If the valve guides were the culprit for oil consumption, wouldn't this result in a smoky exhaust at startup as the oil which seeped down the stems would be burnt in the first 15 seconds of running? Without a noticeable smoky exhaust, I tend to believe the theory that the oil consumption is due to the agressive crosshatching of the cylinder sleeves.

krimson_cardnal
09-18-06, 08:14 PM
Last year I drove my 96DeVille up Cadillac Mountain is AcadiaNationalPark up Maine. Catch the sunrise there [I didn't] and you are the first in the Continental US to see it.

On the way down I dropped into 2nd and allowed the engine to hold the car back to save the brakes and enjoy the wonderful view.

Well once at the bottom I kicked it up into OD and resumed a 40MPH pace. Well I was quite surprised [though not as surprised as the fellow behind me] to see huge white billowing clouds coming out from behind. Whoa!!!

I qiuckly pulled over and poped the hood and looked around. Nothing seemed out of the ordinary, oil was in the hatches, temp was no problem???

I resumed driving and all cleared up. I did post here, but NO ONE bit. My suggestion was valve guides AND infact this might be part of the oil comsumption mystery. There's 32 of 'em for godsakes.

How about a little feed back on the valve guide issue. K_C

std1
09-19-06, 11:29 AM
I spoke to a old race engine builder I know and he suggested finding out what type of piston rings are used on the Northstar. Here is his response: The nature of bore finish has long been a topic of discussion amongst engine builders of all persuasions. For decades, engines used iron or hard chromed steel rings. The latter, in particular, demanded a long break-in period but exhibited excellent life (locomotive and marine Diesel engines use chrome rings, for example). In order to encourage the best possible seal with these ring types during the break-in period, relatively agressive cylinder wall finishes are recommended by engine manufacturers.

The development of barrel-faced molybdenum disulfide coated piston rings for automotive use changed all that (the first widespread usage of this ring type, I believe, was in the Chevrolet 396 big blocks of the mid-1960's). In fact, the developer of the BF moly ring advised that engine builders hone the cylinder walls to a much smoother finish than previously recommended, as a lengthy break-in period was no longer required and the ring would seal better. My racing experience over the years more than confirmed the validity of that advice. In "How to prepare Chevy V-8s for racing" book published by GM in the early 1970's, it was recommended that the cylinder preparation process culminate in the use of polishing pads (similar to crocus cloth in abrasivity) to produce the smoothest possible core finish. They explicitly warned against using a bore finish that was suitable for use with iron or chrome rings, as it would cause rapid wear to moly ring, resulting in high oil consumption and early ring failure.

The whole purpose of the moly coating is to reduce the amount of sliding contact between the metal part of the ring and the cylinder wall. In fact, the ring design was such that under low cylinder pressure conditions (i.e., during the intake stroke) the loading on the cylinder wall was minimized and most of the sliding contact was between the moly coating and the wall. The application of pressure to the compression side of the ring would cause it to twist slightly, thus producing a tighter seal. The rings were marked so the installer could determine which side was up, as accidentally inverting them would result in a huge amount of blow-by. The use of a smooth bore finish promotes this property, resulting in better sealing at high engine speeds, at least up until the point of ring flutter is reached which would not be a problem with the NS as it does not develop a high enough piston speed at redline.

General Motors developed the moly ring and wrote the book on how to use it. IF they are using a moly ring in the NS engine with the coarse bore finish (as discussed by other members in this forum) then it seems that they have either ignored their own research (which does not make sense as many a racing engine has survived with smooth bore finish and moly rings let alone engines designed for street cars) or they have an unaddressed production problem.

chicagobob815
09-21-06, 12:43 PM
My Northstars has always used oil. I add a quart at about the 50-60% of life. I've had two engines. Not a real problem but I do check it now ahead of the "low oil" message.

dkozloski
09-21-06, 12:59 PM
I spoke to a old race engine builder I know and he suggested finding out what type of piston rings are used on the Northstar. Here is his response: The nature of bore finish has long been a topic of discussion amongst engine builders of all persuasions. For decades, engines used iron or hard chromed steel rings. The latter, in particular, demanded a long break-in period but exhibited excellent life (locomotive and marine Diesel engines use chrome rings, for example). In order to encourage the best possible seal with these ring types during the break-in period, relatively agressive cylinder wall finishes are recommended by engine manufacturers.

The development of barrel-faced molybdenum disulfide coated piston rings for automotive use changed all that (the first widespread usage of this ring type, I believe, was in the Chevrolet 396 big blocks of the mid-1960's). In fact, the developer of the BF moly ring advised that engine builders hone the cylinder walls to a much smoother finish than previously recommended, as a lengthy break-in period was no longer required and the ring would seal better. My racing experience over the years more than confirmed the validity of that advice. In "How to prepare Chevy V-8s for racing" book published by GM in the early 1970's, it was recommended that the cylinder preparation process culminate in the use of polishing pads (similar to crocus cloth in abrasivity) to produce the smoothest possible core finish. They explicitly warned against using a bore finish that was suitable for use with iron or chrome rings, as it would cause rapid wear to moly ring, resulting in high oil consumption and early ring failure.

The whole purpose of the moly coating is to reduce the amount of sliding contact between the metal part of the ring and the cylinder wall. In fact, the ring design was such that under low cylinder pressure conditions (i.e., during the intake stroke) the loading on the cylinder wall was minimized and most of the sliding contact was between the moly coating and the wall. The application of pressure to the compression side of the ring would cause it to twist slightly, thus producing a tighter seal. The rings were marked so the installer could determine which side was up, as accidentally inverting them would result in a huge amount of blow-by. The use of a smooth bore finish promotes this property, resulting in better sealing at high engine speeds, at least up until the point of ring flutter is reached which would not be a problem with the NS as it does not develop a high enough piston speed at redline.

General Motors developed the moly ring and wrote the book on how to use it. IF they are using a moly ring in the NS engine with the coarse bore finish (as discussed by other members in this forum) then it seems that they have either ignored their own research (which does not make sense as many a racing engine has survived with smooth bore finish and moly rings let alone engines designed for street cars) or they have an unaddressed production problem.

My understanding is that the north* has a bore finishing process that starts with a coarse honing pattern to hold oil followed by a fine honing process that smooths the peaks into plateaues. The result is the best of both worlds; grooves to hold lubrication and a smooth surface for ring longevity.

JimLucky
09-21-06, 10:32 PM
Thanks for the info. Just returned from Don Mackey Cadillac in Tucson. I spoke with a gentleman who goes by the name of Chuck. He stated that a N* should get about 3000 miles before adding any oil. He went on to say that his customers get their every service done 3000 miles without adding oil between services.


Buddy94


I have a 93 an old one and it just turned 100k I changed the oil when I purchased the car and have put 3k miles on it.During that time I have had to add just 1/2 a qt. I just checked it today before a long drive to the airport and it is still full.I dont see this thing burning realy hardly much oil at all.Maybee I just got lucky. :bouncy: My self personaly a V8 with 100k
and very little oil consumption says a lot about how well this engine was built:thumbsup:N*

xxcaddytech
09-23-06, 04:38 PM
one thing i don't see mentioned here is that the n* uses low tension rings. (mostly used in race engines) it does mean oil consumption BUT it frees up horsepower. and saves the precious cross hatch pattern.. that is tha main reason we see almost no ridge when torn down. its harder to wear out if no pressure is being applied and a thin coat of oil is inbetween the surfaces.. btw how come lexus can build a 24v motors with none of these problems and deadly reliabliity and gm can't?? --i own both--

hkaiman
04-06-08, 03:39 PM
does anyone know of any additives for the oil to help burn off the carbon from the rings?? I hear that the carbon buildup can cause the oil consumption.

krimson_cardnal
04-06-08, 05:08 PM
Periodic WOT added once a month on a quiet open stretch of highway. K_C

hkaiman
04-06-08, 05:42 PM
what can I add to the oil to help burn off the carbon on the rings?? I head this helps stop the oil consumption.

Ranger
04-06-08, 06:04 PM
Go to the top left of this page. Click on Technical Archives and read up. Nothing you can put in the oil will help.

krimson_cardnal
04-06-08, 08:26 PM
Periodic WOT added once a month on a quiet open stretch of highway. K_C

Submariner409
04-06-08, 08:44 PM
hkaiman, .......If you're bound and determined to pour something liquid into your engine one way or another, first Google " top tier gasoline " and read up on Chevron's fuel additive/engine cleaner TECHRON and the gasolines which contain it. Also, follow Ranger's advice and go to the upper black section of this page, bottom left corner, and read the technical Archive, particularly the section on oil consumption. If you still haven't had enough, start going back through this Forum, page by page, and open threads of interest.

krimson_cardnal
04-07-08, 09:30 AM
As has been said check the Archive.

Think of the NorthStar as a cardiovascular system. Put the correct amounts of the right thing in it and exercise to raise the heart rate. It's like the current Cadillac ads say, when you turn your engine on does it return the favor. Raising the heart rate - both yours and the engines is one of the better things you can do for both. WOT once a month keeps you and your NorthStar alive and well. It certainly helps keep the dreaded carbon levels down and gets the rings spinning. The use of any Top Tier fuel will also help keep the gunk out of the air ways and other lost corners allowing a deep breath of fresh air.
Dr. K_C

hkaiman
04-07-08, 11:46 AM
thanks Dr. K_C that was a neat way of putting things.
I will do that..

JohnnyO
04-07-08, 03:30 PM
2000 and newer N*s tend to use less oil than the earlier ones. According to a TSB I had from GM, it is not necessary to add oil unless or until the Low Oil light comes on unless you are going to race it. As mentioned, when changing the oil only add 7 quarts with filter and exercise it once in a while. My mother's '99 burns oil like a two-stroke, my dad's '04 doesn't burn a drop. On the '99 I switched to Valvoline Max Life (although the car does not have high miles on it) and it burns somewhat less oil.

Destroyer
04-09-08, 06:53 PM
Hey,
I am looking for some information on the oil usage of the northstar engine. I am looking at a 2000 STS. If I purchase it, it will be my second Caddy. I have heard that the northstar engine requires a quart of oil every 1400 miles. For the past six years, I have driven my 94 Caddy with the 4.9L from Arizona to Florida with no loss of oil. Does anyone out there have a northstar engine? If so, can you share some information on this topic?

Buddy94I put 10k miles on my '98 Deville, had 88k when I bought it and 98k when I sold it with a blown head gasket(fully disclosed to new owner). It burned a quart of oil about every 3 weeks. I wrote on here about it and found that oil consumption is another bad trait of the Northstar. Basically the Northstar HATES its fluids and spits 'em out one way or another. Oh yeah, they like to leak oil from the bottom too!.

hkaiman
04-09-08, 07:16 PM
I put 10k miles on my '98 Deville, had 88k when I bought it and 98k when I sold it with a blown head gasket(fully disclosed to new owner). It burned a quart of oil about every 3 weeks. I wrote on here about it and found that oil consumption is another bad trait of the Northstar. Basically the Northstar HATES its fluids and spits 'em out one way or another. Oh yeah, they like to leak oil from the bottom too!.


I have a 2000 Deville with Northstar and 70000 miles. It is really using the oil now. It just seems to dissappear. No smoke, no drip. nothing wet in engine.
Just vanishes. I have to add a quart about every 800 to 1000 miles.
I have been finding out this is very common for the engine. Wish I knew that before I bought it....
hkaiman

Submariner409
04-09-08, 07:25 PM
For the flip side of Destroyer's oil coin, my 02 STS uses a quart every 3,500 - 4,000 miles, leaks not one drop, and has not received one ounce of DEXCOOL since 11-21-05, and that includes after a coolant drain and refill last September. I change the oil and filter, fill to halfway up the dipstick hashmark, and that's where it stays for 3 - 5 months.

Lumping all Northstars into the same unhealthy group is patently wrong. Some are mechanically perfect, most are in the middle of the curve, and some are just plain awful. You never hear from the first two groups in a forum: you only get some of the last group represented by people searching for answers.

It has been posted in the performance threads several times by different posters, but I'll post it again: If you try to keep a N* filled to the top of the dipstick hashmark the engine will rapidly get rid of that half quart. RAPIDLY. Run it between the bottom and middle of the hashmark.

tateos
04-09-08, 08:37 PM
Oil is cheap - I don't mind adding it once in awhile - what I do mind are leaks that leave a mess everywhere I go, like I had before I did my HG project and also changed all seals and gaskets, except for the 1/2 case.

Ranger
04-09-08, 09:11 PM
I have a 2000 Deville with Northstar and 70000 miles. It is really using the oil now. It just seems to dissappear. No smoke, no drip. nothing wet in engine.
Just vanishes. I have to add a quart about every 800 to 1000 miles.
I have been finding out this is very common for the engine. Wish I knew that before I bought it....
hkaiman
You wouldn't have bought it just because it uses a little oil? Oil useage is not such a bad thing when you understand it. Go to the top left of this page. Click on Technical Archives and read up on it.

Destroyer
04-09-08, 11:39 PM
You wouldn't have bought it just because it uses a little oil? Oil useage is not such a bad thing when you understand it. Go to the top left of this page. Click on Technical Archives and read up on it.Yeah, right Ranger. Its a good thing right?. You get to add a quart or so of FRESH oil every few weeks and thats good for the motor right?. Bunch of f'ing genius's at GM, I'll tell ya. Every auto maker should put out engines that burn oil.:rolleyes::thepan:

Destroyer
04-09-08, 11:41 PM
For the flip side of Destroyer's oil coin, my 02 STS uses a quart every 3,500 - 4,000 miles, leaks not one drop, and has not received one ounce of DEXCOOL since 11-21-05, and that includes after a coolant drain and refill last September. I change the oil and filter, fill to halfway up the dipstick hashmark, and that's where it stays for 3 - 5 months.

Lumping all Northstars into the same unhealthy group is patently wrong. Some are mechanically perfect, most are in the middle of the curve, and some are just plain awful. You never hear from the first two groups in a forum: you only get some of the last group represented by people searching for answers.

It has been posted in the performance threads several times by different posters, but I'll post it again: If you try to keep a N* filled to the top of the dipstick hashmark the engine will rapidly get rid of that half quart. RAPIDLY. Run it between the bottom and middle of the hashmark.Its an '02........................give it time.:alchi:

ehanso
12-20-08, 07:47 PM
I have a 99 STS with 105,000 miles. It was leaking some oil and found a stripped head bolt. This was fixed and now it uses oil (about 1 quart every 600 miles. Replaced the PCV valve and it uses a little less. before the repair it used maybe a quart every 3,00o miles. Also the mileage has dropped off from about 25 average to 20. It also has stalled 3 times in the last few weeks when I lift off the gas when coming to an intersection. Any comments on how to research this? Thanks

STSj90
12-20-08, 07:53 PM
I have a 99 STS with 105,000 miles. It was leaking some oil and found a stripped head bolt. This was fixed and now it uses oil (about 1 quart every 600 miles. Replaced the PCV valve and it uses a little less. before the repair it used maybe a quart every 3,00o miles. Also the mileage has dropped off from about 25 average to 20. It also has stalled 3 times in the last few weeks when I lift off the gas when coming to an intersection. Any comments on how to research this? Thanks


Check your codes as sub sugested...

Submariner409
12-20-08, 09:41 PM
:yawn: If good ol' Destroyer is lurking, he can take my quote from Post #32 and slide it up here, 8.3 months later. To date, in order to maintain the oil level at halfway up the hashmark, I have added 12 oz. of Pennzoil Platinum 5W-30, and this covers a round trip to CT and another to OH, all highway. No coolant. 3 runs to 132 mph (GPS).

ehanso
12-20-08, 10:42 PM
I did a code check and got some codes B1983, B1344, B1652, B1760, P1599, P1617 and U1064. The ones that seem most critical are P1599 Engine stall detected and P1617 Engine oil level switch circuit. What should I do next?

Ranger
12-20-08, 11:18 PM
I did a code check and got some codes B1983, B1344, B1652, B1760, P1599, P1617 and U1064. The ones that seem most critical are P1599 Engine stall detected and P1617 Engine oil level switch circuit. What should I do next?
Start a new thread.

brmurph
12-20-08, 11:21 PM
I have a 99 STS with 105,000 miles. It was leaking some oil and found a stripped head bolt. This was fixed and now it uses oil (about 1 quart every 600 miles. Replaced the PCV valve and it uses a little less. before the repair it used maybe a quart every 3,00o miles. Also the mileage has dropped off from about 25 average to 20. It also has stalled 3 times in the last few weeks when I lift off the gas when coming to an intersection. Any comments on how to research this? Thanks

My 98 Concours did the same thing. Before the headgaskets blew I was burning 1 quart every 1700-2000 miles, after the headgaskets were replaced it bumped up to 1 quart every 800 miles, 50,000 miles later and still one quart every 800 miles. I agree with some of the post above, I think it is a valve guide problem as the oil seems to build up then releases on WOT, I can WOT every couple hundered miles on a trip and see the smoke.. No WOT no smoke..

Submariner409
12-20-08, 11:26 PM
ehanso, All your codes are benign. Clear them and drive the car. Establish a code history, then begin a new code thread. Remember that when you clear codes the system needs 2 weeks of normal driving to settle out in order to pass an OBD emissions test.

tateos
12-23-08, 02:06 PM
My 98 Concours did the same thing. Before the headgaskets blew I was burning 1 quart every 1700-2000 miles, after the headgaskets were replaced it bumped up to 1 quart every 800 miles, 50,000 miles later and still one quart every 800 miles. I agree with some of the post above, I think it is a valve guide problem as the oil seems to build up then releases on WOT, I can WOT every couple hundered miles on a trip and see the smoke.. No WOT no smoke..

I have seen that smoke too, but I believe it is carbon - it is a black, sooty smoke, not bluish like oil smoke.

I just reached 4,000 miles since my HG project, and I realized I had not checked the oil since then. I was surprised to see I needed to add 2 quarts to get the dipstick back up to 1/2 way between add and full. The low oil message never came on - neither did the low oil pressure. I suppose 2 quarts in 4,000 miles is pretty good at 100K+ miles - everything on the engine is original, except for the head gaskets and bolts and the other gaskets and seals I replaced during the project.

Submariner409
02-03-09, 06:02 PM
:bump:

Took a bit of digging, but this is the perfect thread to share this tidbit............

GM TSB #02-06-01-009C of Oct. 23, 2003 gives quite a rundown on Northstar oil consumption, reasons, fixes, and combustion chamber cleaning. Well worth the read.......maybe one of our techs can post the entire thing....it isn't too long, BUT there are two points that bear repeating and which will raise a lot of eyebrows:

1. The current GM accepted oil consumption figure for a maintained moderate-mileage Northstar engine from the 1996 - 2003 year group is 2000 miles per quart.
2. If the oil level is at the MAX mark, or close, on the dipstick, then the engine is a half quart overfilled and the PCV system will rapidly scavenge the excess oil by sending it to the intake manifold to be burned. (This alone may lead to perceived high oil consumption.)

If you can't wait, subscribe your car to www.alldatadiy.com and read the TSB section. Eye-opener. Actually, anyone who has arrived since mid-2007 should read this entire thread - both pages.

indianavince
06-06-11, 04:57 PM
Errr... My Northstar 2000 SLS with 135,000 is asking for a quart in 300 miles after a couple years of a quart every 1000 and a quart in 2000 back at 80,000 miles. I have "exercised" it... going to try 4 quarts of DELVAC and some more exercise.... I'll update you after that.

Submariner409
06-06-11, 08:11 PM
Errr... My Northstar 2000 SLS with 135,000 is asking for a quart in 300 miles after a couple years of a quart every 1000 and a quart in 2000 back at 80,000 miles. I have "exercised" it... going to try 4 quarts of DELVAC and some more exercise.... I'll update you after that.

Go back and read the entire thread - and post #28. You obviously fall into the "awful" end of the bell curve, while I'm still fortunately in the "over 4,000 miles/quart" end.

Ranger
06-06-11, 10:50 PM
Holy smoking tail pipe Batman. Now THAT"S oil usage. Can't help but wonder if you have some other underlying problem.

Destroyer
06-07-11, 11:15 PM
There has been a lot discussed on Northstar oil consumption. Search in the archives for more info. It's not unusual for a Northstar to use more oil than some other engines. It's a high performance engine and has to allow a little more oil to the top rings for lubrication as as well as down the 32 valve guides.

Design intent for oil consumption would put the engine at about 4000 miles per quart consumption but due to the variables in production parameters there are engines that will use 1 quart per 1000-1500 miles - perfectly normal and acceptable - but more oil consumption than "intended". Nothing will be wrong with the engine but the continuous oil adds are aggravating. If this is the case then understand that the engine is probably going to run a long, long time like that as the cylinder walls, rings, valve guides, etcetera like all that oil that you are putting in and the continuous oil adds fortify the used oil in the sump and replenish the additive package in the oil that is slowly depleted under normal usage.

Comparing the 4.9 to the Northstar is an apples to oranges deal. The 4.9 is an excellent engine for it's purpose but does not offer nearly the performance, durability, fuel economy and emission control capability of the Northstar. The Northstar is a high output engine and likes to be "used".

The best way to minimize oil consumption in a Northstar is to keep the sump filled slightly low (many are continuously overfilled) by only checking the oil level when hot and only filling the sump with 7 quarts of oil (7.5 with a dry filter at a change.) A typical 8 quart fill at a change is "required" to put the oil level on the full mark when cold but is actually overfilling the crankcase promoting oil consumption.

Use conventional mineral oil (synthetic is not required at all) as it tends to provide better oil consumption.

And last but not least, air the engine out frequently. It likes to be used and red-line upshifts at wide-open throttle help promote clean combustion chambers, exercise the piston rings to keep them free of carbon buildup and keep them mobile and to ensure the engine is broken in and maximum sealing is obtained. The Northstar does not like to be babied around. It likes to be run hard frequently with a WOT blast in merging or whatever. Even engines reported to use 1 quart per 1500 miles tend to improve to 2500 miles per quart or better when subjected to a regular schedule of use and "abuse".
Right Anthony. Great advice! Refilling oil and having to beat on a car constantly so it runs good is truly a luxury. Blowing through a quart of oil every thousand or so miles is NOT normal for a ANY motor no matter high performance it is (and don't fool yourself man, a Northstar is not a very high performance motor by todays standards). Constant WOT's is akin to begging for H/G failure.

History has shown the 4.9 to be the superior overall motor as compared with the N*. It's funny to see 4.9 owners state that there cars are not "N* powered" as a selling point when they sell their cars.

drewsdeville
06-07-11, 11:40 PM
History has shown the 4.9 to be the superior overall motor as compared with the N*. It's funny to see 4.9 owners state that there cars are not "N* powered" as a selling point when they sell their cars.

I'm a little biased being a 4.X fan, but I also find them to be superior engines. Of course, they are very basic and aren't nearly as impressive from a technical standpoint, but I think the end result to the user, which is very important, is superior. Rock solid reliability, low cost of operation, great powerband that offsets the low peak power numbers, with mileage that's just as good as the Northstars.

That said, the 4.X couldn't go on any longer, and a replacement was necessary. I thin , fundamentally, the Northstar was the perfect fit. I just think they could have done a better job updating the Northstar's trouble spots (rather than riding them out for 20 years) and it's performance (again, instead of riding it out for 20 years). The Northstar needed a much more significant update than it received in 2000, IMO.

As far as sales ads, I've noticed the same and eventually assumed that the N* has developed a poor reputation for the public outside of enthusiasts.

Submariner409
06-08-11, 10:56 AM
Its an '02........................give it time.:alchi:

BUMP !!! "Time": Is 3 years and 2 months enough ?? .............and nothing - nothing is any different from Post #32. Matter of fact the engine is a regular fuel highway runner, sees about 8,000 miles/year, and the last quart of oil went right at 4,600 miles. No complaints.

RippyPartsDept
06-08-11, 11:51 AM
My N* powered Cadillac has been very reliable in the year+ that i've owned it ...

i've been on two long trips ... alternator is the only major repair that i've done

and i would hate* to have a 4.9 powered vehicle

IMHO the N* is by far the superior engine ... and then on top of that there is all the other technology in my car that is superior to the tech in the 4.9 powered vehicles

* - hate is the wrong word here but is quick and easy so i'll use it even though it might be inflammatory

Submariner409
06-08-11, 01:30 PM
We lose sight that every Northstar failure or shortcoming in these Forums represents a tiny fraction of total FWD Northstar production.

Let's guess, for openers, that over the 8 years of CF there have been 8,000 FWD Northstar threads of problems from 8,000 different posters. That's 1,000/year, a bit high in my estimation.

Quick - as of December, 2003 (the last of the predominantly problematic FWD Northstar production) how many engines were built - TOTAL ???

RippyPartsDept
06-08-11, 01:49 PM
Quick - as of December, 2003 (the last of the predominantly problematic FWD Northstar production) how many engines were built - TOTAL ???
a decade's worth.

... :cool2:


what do i win?

..

counter debate point will state that there's a ton of failures not reported here...

Submariner409
06-08-11, 02:23 PM
counter debate point will state that there's a ton of failures not reported here...

True - but how does one get the true "big picture" for FWD Northstar and assume that no other vehicle engine has problems in order to place the FWD Northstar at the bottom of the heap ???

drewsdeville
06-08-11, 11:39 PM
Sometimes a reputation earned can't be explained - it is what it is. I can't give scientific evidence as to why, but what Destroyer said about John Doe taking the time to advertise that "this is the better 4.9, not the Northstar" certainly occurs on a semi-frequent basis - and that has nothing to do with reported failures or perception on cadillacforums.com .

EDIT: Hell, 10 seconds after opening a craigslist tab I find this, posted today. Perfect example.

http://milwaukee.craigslist.org/cto/2429066862.html

Whatever the reasons, the N*'s reliability reputation, whether it's accurate or not, appears to be lower than average. It's not because "no other vehicle engine has problems".

RippyPartsDept
06-09-11, 09:48 AM
That CL ad doesn't mention anything about one motor being better than the other. It just clearly states which engine the vehicle in the ad has. Since 1994 was a year where there might be confusion on that point it makes sense that they would state clearly which engine is in the car. "4.9L NOT the Northstar" does not sound like an endorsement of one or the other to me

drewsdeville
06-09-11, 10:19 AM
Oh, sorry man, here you go :) :

http://milwaukee.craigslist.org/cto/2422517419.html

I know I used the 4.9 in my '95 as marketing leverage when I sold it :hide: I'll never know if it ever helped or not, but I figured it couldn't hurt.

Submariner409
06-09-11, 10:39 AM
This week it's Northstars and 4.9 GM engines; next week it will be 4.6 Ford OHC's and turbo v-6's. The week after that it will be Mercedes something-or-anothers. My reliability opinion goes to the Olds 455 RWD engine series, but then, engine opinions are like buttholes: everybody has one.

This thread is doing pretty well for 7.5 years old !

drewsdeville
06-09-11, 10:58 AM
Hmm, bottom line reliability opinion? That's really hard to pinpoint for me. I'm gonna have to stay with fuel injection on this one and say the later (post-2002) 2V Ford 4.6. Too bad they were dogs though.

89falcon
06-09-11, 01:21 PM
Sometimes a reputation earned can't be explained - it is what it is. I can't give scientific evidence as to why, but what Destroyer said about John Doe taking the time to advertise that "this is the better 4.9, not the Northstar" certainly occurs on a semi-frequent basis - and that has nothing to do with reported failures or perception on cadillacforums.com .

EDIT: Hell, 10 seconds after opening a craigslist tab I find this, posted today. Perfect example.

http://milwaukee.craigslist.org/cto/2429066862.html

Whatever the reasons, the N*'s reliability reputation, whether it's accurate or not, appears to be lower than average. It's not because "no other vehicle engine has problems".


Hmmm.....
If I'm out shopping for a 15 YO car, I'm doing so to have a nice car that hopefully won't be expensive to keep on the road. If I was shopping for a high performance luxury sedan, I'd be down at the dealer picking up a new CTS-V. Given my "needs", a 4.9 with it's MUCH easier/cheaper rebuild makes MUCH more sense.

RippyPartsDept
06-09-11, 02:06 PM
what about the person shopping for the best cadillac they can find under $6000?? it's not going to be a 4.9L that's for sure

there's a lot of room between a 15YO 4.9L car and a new CTS-V ... lots of northstars in that room

drewsdeville
06-09-11, 02:18 PM
Yeah there are, somebody's gotta buy them. As long as it's not me, I'm happy :) . It's clear that many others out there feel the same. Good thing "best" is a relative term. There's something to make everyone happy. One man's junk is another man's treasure, right?

RippyPartsDept
06-09-11, 02:24 PM
Sucks to be the guy who thought that gold was junk...

although i'm glad that the original owner of my '99 didn't' think it was junk... it sure doesn't look like junk

drewsdeville
06-09-11, 02:28 PM
Exactly, you're getting it now.

Value is relative. I wouldn't be willing to pay as much for a N* Cadillac as you would since I don't want one - and vice versa. It's all subjective.

Submariner409
06-09-11, 02:44 PM
This ol' girl isn't exactly "junk" either -

RippyPartsDept
06-09-11, 04:23 PM
drew,
how much would you be willing to pay for my car?
pics are in my profile
mileage is around 139k

vincentm
06-09-11, 05:12 PM
This ol' girl isn't exactly "junk" either -

Man that is a sweet ride..

-------------------------------------------------------
Sent from my Northstar powered phone

drewsdeville
06-09-11, 11:00 PM
drew,
how much would you be willing to pay for my car?
pics are in my profile
mileage is around 139k


Tough question. Hard to answer the question "what would you pay for something you don't want". That said, I wouldn't give a nickel for it. It's worth nothing to me -how do I put a price on a car I don't want to own? A car's value is not what KBB says, it's not what the average on the market is, it's not even what you think it's worth: it's what you can sell it to the projected buyer for. The buyer controls the price.

In this case, me being the projected buyer, it's worthless.

RippyPartsDept
06-10-11, 10:53 AM
good answer (i guess) ...

maybe i should have asked what you thought my car was worth
(but i suspect i'd get the same or similar answer)

drewsdeville
06-10-11, 11:10 AM
What do I think someone else would pay for it? 140k mile, 12 year old Cadillac, k-body Deville... I don't know, $3k or so sounds fair to me. Why do you ask?

RippyPartsDept
06-10-11, 12:04 PM
Just curious for the opinion of someone who thinks that they're not worth much... i've been told (and seen on used car lots) that it's worth 4-5 grand

i don't plan on selling it any time soon either... i'm not really into flipping cars, but i only paid $2800 for it a year ago

Submariner409
06-10-11, 12:15 PM
For better or for worse, the "worth" (and cost) of an object - cars be damned - is what the market says it is. Personal opinion has absolutely no say in the matter. Someone pooh-poohs your wares and tells you that whatever you're selling is worthless, you look them in the eye, ask them to FO, and look elsewhere.

People like that know the cost of everything and the value of nothing.

I'm trying to sell a condominium boat slip in a depressed boating market. The brokers and tax assessors say it's "worth" $55,500. I'll be lucky to get $45k, tops.

tigers2007
06-10-11, 12:27 PM
I'm surprised no one has brought this up in this thread yet; and its a question I've had for a while: if my car is burning a quart every 1000 to 1500 miles, then can I extend my oil change intervals? Right now I'm doing Rotella 10W-30 and PF61 filter every 4000 and the car is at the 4k mark. So at this point, half the oil is "fresher" than whats left from the original 7qts. This car is my freeway-commuter for my 75 mile r/t country-to-the-city ride (95% expressway).


For all of those potential Northstar Performance customers, I had jake stud the engine and I think I have put on about 9000 miles and its been running perfect. Last week it was in the 90's and it never went above 222 degrees (95MPH on a 95 degree freeway for 15 minutes). If i'm driving like I normally do, it is at 200-208 when I'm 65MPH and cruisin. I have done MANY WOT's in this beast too.

Submariner409
06-10-11, 12:29 PM
If this is the '99, you can easily go by the Oil Life Monitor. Even with NO oil usage, 4,000 miles, particularly 4,000 miles of suburban/highway driving, is WAY too early to change the oil & filter.

You are getting less engine wear in a year of freeway driving than in a month of city driving. The Shell oil is just perfect for the '99.

Highway driving: Different car entirely, but my one of my daughters drives over 35,000 miles a year, all highway and Interstate. She just traded a Honda Civic in on a Hyundai Sonata. The Civic had 276,000 miles on it, was quiet as a mouse, and used not a drop of oil. Normal maintenance only - the head had never been off. My 1995 F-150 I-6 had 140,000 on it when traded. Perfect condition, all highway.

tigers2007
06-10-11, 12:38 PM
yeah thats what I was thinking. My dad and I were wondering if we technically have to ever change it at all as it gets refreshed 15% almost every 1000 miles. This car works perfectly and looks perfect. Maybe I can be the guinea pig and never do another oil change on it (maybe just a filter every 10k). Even though this car looks and drives new, its a beater and has no value to my father and is only a MPG-machine for me as my truck on gets like 18 on a good day.

RippyPartsDept
06-10-11, 01:21 PM
i would theorize that if you're adding oil between oil changes that yes you could extend your interval past the 0%

BUT

i still wouldn't... because some of the oil (probably most) will be past 0% and even though the OLM has a 100% safety built in you don't want to risk it

i wouldn't have any qualms about going all the way down to 0% though

Submariner409
06-10-11, 01:28 PM
Yeah that ^^^

Just because the engine consumes (and/or leaks) some oil doesn't mean that adding oil "refreshes" the remainder - in addition to anti-wear additives, oil suspends and cleans dirt, soot, and wear particles from normal engine wear and use. When you change the oil and filter, preferably immediately after a long highway run, all the nasties are suspended in the oil and the drain action cleans out the contaminants. Todays metallurgy and engine buildiing techniques, as well as oil chemistry, allows oil changes to be spaced a LOT farther apart than when I was a new driver.

Back in the 50's and 60's the Kendall Oil two-fingered fist logo originally stood for "Kendall - The 2,000 mile oil". Times, they are a'changin'.

tateos
06-10-11, 06:19 PM
The car is nice...but I still say I LOVE the front yard Sub!

Submariner409
06-10-11, 06:24 PM
The car is nice...but I still say I LOVE the front yard Sub!

Tks..........Just beyond the big oak tree over the car hood we have a 100 yard rifle range that goes down the clearing to the right.

CadillacLuke24
01-27-12, 05:54 PM
O.k. gotta get my 2 cents in on this one, althought the thread is old. Got me a 96 Deville VIN Y in October of 2008 from Cadillac of Sioux Falls (SD). Had 38,947, now she's got a tick over 65. Always kept the oil within range (at the "halfway" mark), and I do change it nearly on the dot at 3,000. I'm a 21 year old with a lead foot, so the WOTs are no issue. Doesn't burn a drop of oil, doesn't leak, and she runs like a top (save the aging plugs). The 4.9 is a decent motor, and it's a whole different ball game compard to the N*, but it just doesn't offer the performance, economy, and enjoyment :sneaky: that the ol' N* does. Is the N* flawed? Probably not. IMHO, it's more of a negligence issue on the part of the less-than-enthusiastic owners out there. Sure, it's not the hottest thing out there, but it will shame 95% of the stuff out there. Besides, who says you can't tune the PCM or engineer some new direct injection heads? :D

Submariner409
01-27-12, 05:59 PM
Trouble with DI heads on a Northstar is the central spark plug location surrounded by 4 valves - and up top, cams and valve springs/retainers around the plug well.

Talk to AJ or Lynden Wester about tweaking the PCM on that early OBD-II engine.

CadillacLuke24
01-28-12, 03:31 PM
Darn it, I forgot about that :banghead: I will be doing the PCM tuning though. :D

Submariner409
01-28-12, 04:10 PM
DO NOT expect any miracles - or even close - on a VIN Y drivetrain tune. The single best "performance" mod - and it will get you maybe 2 - 3 hp - is a custom bent cat-back exhaust system. $$$$.$$

Mark D
01-28-12, 11:22 PM
I came into this thread late, and have not taken the time (because I don't have that much time) to read all the posts.
But I have read the first few and some others.
I thought I'd add this insight, or maybe I should call it my own experience with oil consumption.

First, I have a '95 VIN9 in a STS that has 227K miles on it. It uses about a half quart of oil between changes at around 4000 miles.
Second, I have a '98 VIN9 in a STS that has 200 K miles on it. It's the car I just did head gaskets on.
We (wife and I) got that car with about 95K miles on it back in 2002. It burned about a quart of oil in 800 to 900 miles.
But as time has gone on, the consumption continued to drop to the point where it now burns about a quart in 2500 or so miles. To me, a guy who's used to cars from the '60s and 70's where typical consumption was a quart in 1000 miles, or less, this is just fine.
At least it has gotten better, not worse.
Is adding a quart of oil every few weeks that big of a deal? At least knowing you need to check the oil will get one to open the hood and look around for any unknown maintenance issues that might be coming up, like antifreeze leaking, worn belts, etc. A contientious car owner will check things under the hood at least every week or so, won't he? Perfect time to check the oil and add if needed.
It'll burn less if you don't top it right to the top of the dip stick markings.
Mark D.