CG-4 or CH-4 or CI-4 ? ? ?

[CleviteKid]

I have noticed some apparent concern over truck owner's manuals that require CG-4 or CH-4 oil, and whether or not it is appropriate to use CI-4 oil in them.

The American Petroleum Institute lists backward compatibility for each new classification as it is introduced. See http://api-ep.api.org/filelibrary/Guidechart2002.pdf

In particular, CI-4 motor oil:
"Can be used in place of CD, CE, CF-4, CG-4 and CH-4 oils."

Good thing, because the visor label on my 1984 truck requires CD oil. CD oil was introduced in 1955 (!!) and was replaced by CE oil in 1987.

As I have mentioned in the past, GM did NOT send me a new visor label, and a new owner's manual each time the API upgraded oil specifications.

By the way, even though CD and CE specs are obsolete, CG-4 and CH-4 are still current, even with the introduction of CI-4. So use any of these three grades of oil in your diesel engine, and live long and prosper.

Dr. Lee :cool:

[Professor]

The other night a customer came into the store requesting Dexron II. I explained it had been replaced by Dexron III and was approved for use in his application. He replied

[SteveO]

Thanks Dr Lee..

I guess people don't understand that the latters are in Alphabetical order, as a new rating is introduced it's the next letter in the ABCs smile.gif

[HDLD]

Perhaps this is a case of a little information can be harmfull...but I recall that CI-4 was released to deal with EGR in the 2004+ model years.

Is it possible that although they are backwards compatible, that the CH-4 is in fact slightly better for our vehicles?

[ZFMax]

From http://www.mobil.com/USA-English/Lubes/Product_Information/Diesel_Engine_Oil_FAQ.asp

22. Can you explain the difference between API service categories CD, CD II, CE, CF, CF-2, CF-4, CG-4 and CH-4?
The American Petroleum Institute (API) has developed a two-letter code to describe quality levels in both gasoline and diesel engine oils. These codes are used by the engine manufacturers in their owner's manuals to identify the appropriate quality of oil to use in their specific engines. The codes can typically be found on the bottle labels for quarts or gallons of engine oil. The C codes are for compression-fired diesel engines. The S codes are for spark-ignited gasoline engines.

Oil quality levels are developed through broad industry agreement involving the oil suppliers and the engine manufacturers. Over the past decade, changes in diesel engine oil quality levels have been primarily driven by restrictions on diesel engine emissions. The Environmental Protection Agency (EPA) upgraded Clean Air Act (CAA) regulations in 1988, 1991 and 1994. Oil quality (and engine technology) changed in response to these regulations. The most recent implementation date for CAA regulations was in 1998 and the API has established API CH-4 performance levels to address the lubrication needs of engines designed to meet the new EPA emission requirements. In October 2002, most diesel engines will require API CI-4 oil to address the demands of this lower emissions configuration.

Here is a short description of the diesel engine categories, starting with the most current:
CI-4 has been developed to establish a standard for oils that are intended for EGR equipped engines as well as satisfying the needs of engines requiring CH_4, CG-4, CF engine oils. This new CI-4 engine oil category establishes the highest level of oxidation resistance, total base number (TBN) retention and soot dispersancy ever set for an API category.

CH-4 has been developed to address engine design changes required to meet new 1998 EPA emission standards. The performance requirements include handling even higher soot loading than CG-4 rated oils and passing a series of new engine test protocols.

CG-4 was developed for oils used in 1994 and later low-emission, high-speed, four-stroke cycle diesel engines. It is also typically used for diesel engines using low sulfur diesel fuel. Newer engines that are used for on-highway or off-highway applications may call for CG-4 quality oils. One of the main advances in CG-4 verses previous quality levels is the ability of the oil to handle high levels of soot that is generated by some of these low emission engines.

CF-4 was established in 1991 to specify oil quality for severe duty, low emission, four-stroke diesel engines produced in 1991 or later. Oils meeting this category offered improved control of oil consumption and piston deposits verses previous quality levels. CF-4 has essentially replaced the CE quality rating.

CF-2 was established at the same time to specify oil quality for severe-duty, two-stroke diesel engines. CF-2 has essentially replaced CD II.

CF was established for service typical of off-road, heavy-duty diesel engines and engines operating on higher sulfur fuels. The CF quality level essentially replaced the CD level.

CE was established in 1988 to specify oils for severe duty diesel engines with turbochargers. This rating is essentially obsolete and oils meeting CF-4 are now used in applications calling for CE oils.


*********************

My take from reading it: the different ratings address different things, and do not necessarily supercede each other. But that's just my interpretation, I could be wrong.

[george morrison]

Regarding the question "is CH-4 really a better oil for us?" As Dr. Lee has explained the CI-4 is an evolutionary advancement, primarily formulated to deal with the higher temperatures and stress imposed on engine oils as a result of the new EGR installations. We are actually the beneficiary of this as the CI-4 oils are superior in every measurable parameter vs. the CH-4 oils. A LOT more superior in oxidative stability, soot holding, viscosity stability, anti-wear, acid neutralization, shear stability, and on and on..
George Morrison, STLE CLS

[HDLD]

Thanks, George. That was helpful. I wonder when Delvac 1 will be available as CI-4?

[CleviteKid]

Look at the API licensing website:
http://www.api.org/cgi-bin/eolcs_li.cgi?o=C&b=delvac

and you will find that Mobil Delvac 1, in 5w-40 viscosity, is rated as:

CF, CF-4, CG-4, CH-4, CI-4 / SL

Your wish was Mobil's command, Delvac 1 is now rated as a CI-4 engine oil.

Dr. Lee :cool:

[CleviteKid]

PS:

The SL rating on Delvac 1 means you can also use it in your wife's Mercedes convertible, Lincoln Navigator, Seville STS, etc. etc. etc. if you are so inclined.

Yes, I know, the viscosity is higher than the car companies recommend, but the engine will last longer. And you can tell her you treat her car just as well as you treat your truck :rolleyes: .

Dr. Lee :cool:

[george morrison]

I apologize for it being not Duramax related but Delvac 1 relevant, but with Dr. Lee mentioning "Seville STS" as in oil pan leak: I switched my wife's Seville STS over to Delvac 1 a year ago in an attempt to put off the dreaded "pull the engine to change the oil pan gasket $1500 repair bill" that is endemic to many Northstar engines. The leak soon stopped, oi consumption reduced to nil, and she is happy that the oil spot on the driveway is gone.. Remembering from the past the stories of "synthetic cause oil leaks": well here is a success! In more ways than one...
George

[CleviteKid]

Dr. Lee:

. . . . knows all . . . sees all . . . tells some of it. . . . . .

. . . so be careful . . . my correspondents are everywhere . . . . . :eek:

Dr. Lee :cool:

[hoot]

FYI.....

As SteveO stated...

In the API naming program, the second letter progresses up the alphabet with each new category. Logically, the letter

[ct0218]

I got 2-2 1/2 gal bottles of Amsoil 15W40 full synthetic in December and it showed a CI-4 specification.

[konacat]

Just ran across Pennzoil

[mackin]

Pennzoil

[dmaxstu]

As Geo.Morrison I also apolagize for asking a non Dmax question. My Honda 2000eu generators call for 10W-30 oil with the APIservice classification SJ. I can't seem to be able to find a synthetic other than Mobil 1 delvac 5W-40 that I use in the D/max with that classification. Could you E-mail me at hlbrsma@aol.com and guide me George? Stu

I promise not to post non D/max stuff here again.