: API grades



Jan Olsson
05-08-06, 03:10 PM
Hi everyone!

Iīm a newbie here so I thought Iīd say hello, proud member of Caddyinfo too I might add.

I got some questions about oil...donīt wanīt to start another debate here. :thehand:
My -93 STS requires 10W-30 oil API service grade SG, but since the current grade is SM I got a few questions.
Am I right about grade SM being better or at least being equal to grade SG with respect to wear? If that is the case, is it also ok to fill my -88 Eldo with it? My Eldo requires grade SF.
The reason Iīm asking is because Iīve seen posts about filling 4.9 L with 15W-40 oil with a higher degree of ZDP (ZDDP) eg "diesel oil" to get better protection against wear for the distributor gearing etc.
Why is it necessary to do that if the grades are getting increasingly "better"?:confused:
Isnīt the backward compatibility in SM reaching down to SF, SG or what?

Please excuse my bad english.

Janne

chevelle
05-08-06, 04:11 PM
Your english is fine. Better than my German or whatever.....LOL

You are correct in assuming that the later API grades such as SL or SM are "better" and , as such, supercede the earlier grades. That is conventional wisdom and is pretty much the case as one of the API requirements is that "improved" performance grades supercede prior grades and are always backwards compatible.

Having said that.....the current crop of oils "rated for gasoline engines" that are on the shelf in the most obvious locations in the stores are also "fuel economy" oils. Any oil with the ILSAC "starburst" symbol that says "for gasoline engines" is a bit of a hybrid....those oils meet the latest API performance specs, have the minimum allowable ZDP (to prevent catalyst contamination) and have friction modifiers in the oil for fuel economy improvement.

The difference is that the API specs just relate to the oil's performance as tested on gasoline engines. API specs have nothing to do with friction modifiers or MINIMUM ZDP levels. The API specs just have minimum performance specifications based on actual engine testing.

Understand that the API performance specs have a lot of requirements besides just "wear protection". Most all of the improvement in the latest grades is in the area of temperature protection. The latest oils will still perform at hotter and hotter engine temperatures. So they are "better" in that the older oils might start to oxidize and give up around 290 degrees F and the latest oils will still function well at 310 or 315 degrees F. They are not "better" in that they give more wear protection.....they just have better high temperature resistence, among other things.

More modern, current production engines are designed to run with the minimum ZDP oils and friction modified oils. Clearances are changed, designs are changed to add roller followers everywhere that are not ZDP dependent for preventing wear, wear surfaces are hardened where necessary, etc.....

Older engines designed for the SF and SG oils that had more ZDP in them are not as well protected against ZDP depleted oils.


So...technically the older engines should be OK with the new SM oils since the SM oils "technically" supercede the older oils and are backwards compatible. But the newer oils probably are " barely" adequate in terms of anti-wear additives such as ZDP. If the engine is perfect inside it will likely be fine. But if the engine is marginal for wear the ZDP depleted oil MIGHT cause a problem and accelerate wear. Certainly you would not want to use the newer ZDP reduced oils for long change intervals in the older engines.

An older 93 Northstar, for instance, has 32 rubbing element tappets (flat tappets) that require much more ZDP for protection against wear than the 2000 and later Northstars with roller tappets.

If you want to be sure your engine has the best wear protection you can do two things. One, use one of the non-"gasoline engine" oils such as the diesel Rotella or Delvac or Delo oils. Those oils have much more anti-wear protection since they are also certified for diesel use. The other thing you can do is to spike the oil you are using with extra ZDP by adding a pint or quart of GM EOS (General Motors Engine Oil Supplement). The EOS is available at any GM parts counter and is sold as an assembly lube. It is basically plain motor oil with a high concentration of ZDP that will fortify any crankcase fill with the extra ZDP desired for more anti-wear protection. It is the only oil "additive" I would ever recommend as it is specifically designed for this purpose.

If you look at the container of Rotella/Delvac/Delo oil you will see in the fine print that it meets all the API diesel performance specs (combinations of the letters CC and CD, etc.) AND it meets the latest gasoline API performance specs such as SL or SM. Now look at the ILSAC "for gasoline engine" oil across the isle in the autoparts store. Read the fine print. It meets the API gasoline SM specs but does NOT meet any of the diesel performance specs. The diesel specific oil is a much "better" product in terms of wear protection if your engine needs it. Diesels have a much greater need for anti-wear protection due to the soot and combustion byproduct contamination of the oil due to the high compression and high cylinder pressures of the diesel engine, so the oils for diesels have to be much better.

I would recommend the Rotella/Delvac/Delo oils for the 93-99 Northstars, personally. The latest ILSAC fuel economy oils are getting very low in ZDP concentration. Fine with the newest engines on the road but not so fine for a 93 Northstar.

You can get the Rotella/Delvac/Delo oils in 10W30 for your engine but they are much harder to find. Check a truck stop or large equipment supplier. If all you can find is the 15W40 version of the Rotella/Delvac/Delo that is fine in the 93 Northstar. The oil is not that much thicker to hurt anything unless you live in the far north and need to cold start at -40.

The other option is to use one of the "severe service" oils marketed by Mobil that are designed for longer change intervals and marketed as such. If you read those bottles you will notice that they also do NOT meet the ILSAC "for gasoline engine" use as they do not have the ILSAC starburst symbol. That is because those oils designed specifically for longer change intervals also have more ZDP in them that excedes the amount allowed for the ILSAC starburst designation.

I would recommend the conventional diesel Rotella/Delvac/Delo oils. I personally use the Delvac (Mobil) in most everything around the house.

Jan Olsson
05-08-06, 06:29 PM
Thanks! Great info :bouncy:

Feels a bit awkward to use "truck oil" though :worship:

peteski
05-09-06, 05:48 AM
Yeah, but trucks usually get very abused and most of them have engines which last for hundreds of thousands of miles without rebuilding.

That's something to think about... maybe it is the oil that they use. Why not use their "secret weapon" in our cars? :D

Peteski

chevelle
05-10-06, 01:07 AM
Yeah, but trucks usually get very abused and most of them have engines which last for hundreds of thousands of miles without rebuilding.

That's something to think about... maybe it is the oil that they use. Why not use their "secret weapon" in our cars? :D

Peteski

My brother's Detroit Diesel in his tractor is warrantied on the lower end for 500,000 miles..... It also holds about 12 gallons of oil for the engine. THAT is also how they can run for so long with high mileage oil changes. They carry LOTS of oil in the system...and run huge oil coolers that keep the oil temperature constant regardless of load or ambient. There is a lot more than just the oil...but the diesel oil is definitely very good, no doubt.

Patrick7997
05-12-06, 12:48 PM
Chevelle, that's a great post. Thanks for the info. I had no idea..... I've heard people say they're using Rotella, but they could never tell me why in a coherent manner.....

Thanks man.

AlBundy
05-13-06, 02:59 PM
Chevelle, that's a great post. Thanks for the info. I had no idea..... I've heard people say they're using Rotella, but they could never tell me why in a coherent manner.....

Thanks man.

I also thank you. I always learn something new from your posts. :worship:

eldorado1
05-13-06, 10:08 PM
I wonder if it's worthwhile to attempt to find the 10W-30 rotella T oil?

parts68
05-14-06, 12:06 AM
I keep a couple of gallon jugs on hand for my John Deere.
Got it at Walmart

eldorado1
05-14-06, 09:15 PM
Thanks. Picked up some 5W-40 synthetic (blue bottle) rotella. $15 for a gallon. That 10W30 must be impossible to find..

Patrick7997
06-03-06, 10:28 AM
I put Delvac 15W40 in the ETC, as Chevelle suggested.... $8 a gallon at Wally World....

Running real smooth... at a stoplight, I'm not sure if it's running or not, it's settled down so much.....

And yeah, Chevelle, I see what you mean about some of the "extended interval" oils.... they DON'T say "energy conserving II" on them, or have the "For gasoline engines" starburst on the front.... never noticed that before....

Geez, if I get any smarter, I'm gonna be dangerous....:eek:

chevelle
06-04-06, 12:05 AM
I put Delvac 15W40 in the ETC, as Chevelle suggested.... $8 a gallon at Wally World....

Running real smooth... at a stoplight, I'm not sure if it's running or not, it's settled down so much.....

And yeah, Chevelle, I see what you mean about some of the "extended interval" oils.... they DON'T say "energy conserving II" on them, or have the "For gasoline engines" starburst on the front.... never noticed that before....

Geez, if I get any smarter, I'm gonna be dangerous....:eek:


Carefull.....standing there in the oil aisle in Walmart and reading all the labels wil cause people to look at you real funny....as probably cause them to start asking which oil they should use.... LOL LOL

mtflight
06-12-06, 04:55 PM
I put Delvac 15W40 in the ETC, as Chevelle suggested.... $8 a gallon at Wally World....

Running real smooth... at a stoplight, I'm not sure if it's running or not, it's settled down so much.....

And yeah, Chevelle, I see what you mean about some of the "extended interval" oils.... they DON'T say "energy conserving II" on them, or have the "For gasoline engines" starburst on the front.... never noticed that before....

Geez, if I get any smarter, I'm gonna be dangerous....:eek:

I am going to look for the elusive Rotella 10W30. I guess the 15W40 is okay to use on a 98 L37, but is there a fuel economy hit?

Ranger
06-12-06, 10:25 PM
I am going to look for the elusive Rotella 10W30. I guess the 15W40 is okay to use on a 98 L37, but is there a fuel economy hit?
If there is, I doubt it would be enough to notice without some sofisticated instrumentaion.

Patrick7997
06-13-06, 01:21 PM
I'm getting identical mileage with the Delvac 15w40..... I was formerly using Mobil One 10w30....

eldorado1
06-13-06, 01:28 PM
I am going to look for the elusive Rotella 10W30.

good luck. I can tell you it's NOT at walmart, advance auto, or autozone. Try tractor supply, that would've been my next stop.

mtflight
06-13-06, 02:57 PM
good luck. I can tell you it's NOT at walmart, advance auto, or autozone. Try tractor supply, that would've been my next stop.

eldorado1, from your engineering background perspective, what say you about 15W40 on a car spec'd for 10W30?

Any theoretical cons?

eldorado1
06-13-06, 03:25 PM
I wouldn't use it if you live up north. I used to live in MN, where using a thin synthetic oil could mean the difference between your car starting or not.

I don't know if I'd ever switch from synthetic now, as I mentioned I'm running the 5w-40 rotella synthetic. It's more expensive, but it's still cheaper than mobil 1. Other than that, I don't know much about how different viscosities affect lubrication. I figure it's best not to stray too far from the mfr's recommendations.:thumbsup:

Submariner409
06-13-06, 10:11 PM
Something else to think about with engine lubricating oils........oil temperature. If you get squirrelly and lower engine oil temp below 215-220 deg.F, hot highway, the nasties never get hot enough to vaporize and get sucked up by the PCV system. That's one reason why older engines with "open" ventilation systems and "road tubes" tended to build up incredible amounts of sludge and white snot.

mtflight
02-08-07, 11:47 AM
Can anyone confirm that the brand new Rotella T "triple protection" has reduced ZDDP levels?
http://www.shell.com/home/Framework?siteId=rotella-en&FC2=/rotella-en/html/iwgen/press_release_2006/zzz_lhn.html&FC3=/rotella-en/html/iwgen/press_release_2006/cj-4_intro_1006.html


Can the camshaft on a 93-99 Northstar be exchanged from a flat tappet to the 2000+ Roller finger follower?

I have a ticking sound that sounds like a knock sometimes... coming from the right head (by the firewall). It's probably a lifter/spring/valve, from it's location... maybe a worn lobe or tappet??

Is the GM EOS assembly lubricant (PN 1052367), currently sold in a 16-ounce plastic bottle, the same product as the 4-ounce bottle of GM camshaft and lifter prelube (PN 12345501)
I plan to use it at every oil change, and wonder how much of it I should add (advice, recommendations, requested and appreciated!).

Ranger
02-08-07, 05:37 PM
"Can the camshaft on a 93-99 Northstar be exchanged from a flat tappet to the 2000+ Roller finger follower?"

I doubt it.

mtflight
02-08-07, 05:49 PM
GM EOS assembly lubricant (PN 1052367), currently sold in a 16-ounce plastic bottle, how much of it I should add?

I answered my question at http://www.cadillacforums.com/forums/northstar-performance-technical-discussion/97572-oil-weight-4.html#post971843


I just picked up a pint of EOS @ $8.79
Funny that the invoice says it is discontinued?!
(or maybe that's not funny because it could be reformulated to have less ZDDP????)

clarkz71
02-08-07, 06:10 PM
(or maybe that's not funny because it could be reformulated to have less ZDDP????)


No it's the same, that's why the label says "engine assembly lube" now instead of Engine Oil Supplement

mtflight
02-08-07, 06:21 PM
No it's the same, that's why the label says "engine assembly lube" now instead of Engine Oil Supplement


Whew! Thanx.

jadcock
04-17-07, 02:28 PM
I'm digging an old thread up here, but wanted comments on 15W-40/5W-40 oil on the 2000+ engines. I put some 15W-40 oil in the '97, and it seems to really like it. There should be no reason I couldn't also use it, or at least the 5W-40, in my '01 right? I live in NC, so the coldest it gets around here is 20*F, and then, only occasionally.

mtflight
04-17-07, 03:09 PM
I'm digging an old thread up here, but wanted comments on 15W-40/5W-40 oil on the 2000+ engines. I put some 15W-40 oil in the '97, and it seems to really like it. There should be no reason I couldn't also use it, or at least the 5W-40, in my '01 right? I live in NC, so the coldest it gets around here is 20*F, and then, only occasionally.

The whole purpose of Rotella or Delvac 15W40 on the 93-99 Northstar were the ZDDP levels. The 2000+ has a different head design which does not require the ZDDP to survive.

eldorado1
04-17-07, 04:09 PM
Can't hurt..... Might make the cam chains last longer or something... ;)

Submariner409
04-17-07, 09:29 PM
Don't forget......whether it's 5w-20 or 15w-40 the low number is the cold flow viscosity and the high number = the hot. Our engine oils are flow controlled with bypass valves and temperature controlled by in-radiator oil coolers. Therefore, if your thermostat sets coolant at 190 deg., then your oil will run somewhat warmer. YOU WANT OIL TO RUN ABOVE 212 deg.F in order to boil off condensates and volatile solvents from gasoline vapor washing. Condensates ????.....the PCV system guarantees that quite a bit of outside air circulates through the engine. What happens when you shut down after a 4 hour run in rain?......the high humidity air remains in the engine crankcase etc. and condenses on all metal as the engine cools.......BTW....What if a bearing surface has to wear enough to allow 40 weight oil to flow through, or at least wet the surface???? What happens when you go back to a 20-30 weight??? If you obsess over ZDDP, mix a 1/2 pint of GM EOS in your next oil change, or, if after '00 or so, don't sweat it.

jadcock
04-18-07, 12:11 PM
'K...I think I'll just use the 5W-30 Castrol GTX then. It seems to be formulated on the thicker side of a 30W oil. I don't necessarily obsess over the ZDDP in particular...I just like the idea of using a HD oil in the car. If I could find any of the HDEOs in 10W-30, I'd use that for sure.

I've been driving the '97 this week to burn some fuel off before the transport. I put 15W-40 Mobil Delvac in it on Sunday, to help control the already small leak and provide good and thick oiling for the hot AZ summer that it's about to encounter. The engine (admittedly plenty broken in at 157k miles) REALLY likes that oil. It seems to run smoother and quieter. After that '97 goes to AZ, the highest mileage car in the house will have 75k miles on it (our van), so I know that none of the engines "need" a thicker oil than 10W-30. I just liked that Shell Rotella T Synthetic 5W-40 -- a great oil at a good price.

But I know that any of the mainstream oils are good, and will settle on Castrol GTX probably.

fubar569
04-19-07, 03:27 AM
i think i might have found a lead on where to get shell rotella T in 10w-30

http://www.pam-companies.com/
1-800-456-2660

looks to be a big wholesaler of some sorts for all kinda of goodies, but under products - lubricants - select shell and hit go...and it gives you an item number for the rotella T in a 6 1 gallon bottle case, 12 1 gallon bottle case, and a 55 gallon drum!

w00t! - thats if they'll sell to us regular joes

jadcock
04-19-07, 07:52 AM
Thanks for that link. In looking at all the product data sheets for various oils, it actually appears that Castrol GTX High Mileage is what I want. It'll have higher levels of ZDDP and anti-wear additives, and it's also formulated pretty thick. Almost a 35W oil if you will, at least according to the viscosity.

fubar569
04-19-07, 11:13 AM
Thanks for that link. In looking at all the product data sheets for various oils, it actually appears that Castrol GTX High Mileage is what I want. It'll have higher levels of ZDDP and anti-wear additives, and it's also formulated pretty thick. Almost a 35W oil if you will, at least according to the viscosity.

i used to use regular GTX in a talon TSi AWD that i beat the everliving snot out of...i thought it performed admirably...

fubar569
04-19-07, 11:34 AM
FOR THOSE OF YOU WITHIN A REASONABLE DRIVE OF OLEAN, NEW YORK:

THIS DISTRIBUTOR HAS ROTELLA T 10W30 IN STOCK! - and can orderit in if you want...

it is 57.xx per case of 6 1 gallon bottles - works out to 2 dollars and change a quart if my math is right...

Sandburg Oil Company
1641 Olean Portville Road
Olean, NY 14760
Phone: 716-372-4444
Fax: 716-372-3430

i plan on grabbing one...my caddy is due real soon

jadcock
05-05-07, 08:05 AM
I posted this in another thread, but to follow up... BLUF: check the shelf tags at your local Wal-Mart and ask for the 10W-30 Rotella by name. They may indeed have it "in the back" like mine did.

Just wanted to follow up that I found Shell Rotella T in 10W-30 at my...local Wal-Mart. I scoured the shelves before and never found it. Still didn't see it yesterday. But for whatever reason, I started looking at the shelf price tags and noticed that the tag for the 30W Rotella actually said 10W-30 Rotella. Bingo...I had a SKU, so I knew they at least had it in their system. I asked the girl to check in the back and they had a whole pallet of it back there. None on the shelves...

It was a little under $10 for the 1 gallon jug, or $2.50/qt. Great price for a great oil.

eldorado1
05-05-07, 09:39 AM
Maybe, but it's not synthetic.

Patrick7997
05-05-07, 11:32 AM
Eldorado1, I'm not sure anyone ever said it was synthetic.... we were mainly trying to find the 10w30 grade, in the conventional Rotella product...., vs the 15w40 conventional Rotella oil.If I recall, you are using and liking the 5w40 synthetic Rotella variation, which is the only synthetic Rotella I've heard of...

jadcock
05-05-07, 12:45 PM
Maybe, but it's not synthetic.

True. But it's not Amsoil either, so it'll probably ruin your engine either way! :lildevil:

I care less about conventional vs. synthetic. I'm not comfortable running a thick 40 wt oil in a 2001 engine with less than 60,000 miles. I really wanted to find the Rotella in 10W-30...glad I finally did.

clarkz71
05-05-07, 05:06 PM
I picked up two cases at O'Reillys.


http://i86.photobucket.com/albums/k120/clarkz71/Rotella10W-30.jpg

jadcock
05-05-07, 06:02 PM
Since the Rotella 10W-30 meets the SM service classification, does that necesarily mean that it's as low on ZDDP as other consumer grade SM oils? I thought the SM service classification necessarily meant a big reduction in ZDDP, but from the MSDS, it appears that it's formulated into the Rotella 10W-30 in healthy quantities.

clarkz71
05-05-07, 06:06 PM
It's a CJ-4 and has a little less ZDDP then last years CI-4. But it's still has way more ZDDP then regular gasoline only API starburst SM oils.