Shields up!

I almost mentioned this in my reply to Rick Jordon's poll on oil brands, but he asked us to leave out the opinions. So, here I am on a new topic.

Those of you using Mobil 1 oil in your Diesel engines, please check the ratings. That oil is not rated for Diesel engines and Mobil does not recommend it. This was verified when I called the Mobil consumer information line last year.

Mobil makes two oils that are recommended for our Diesels - Delvac and Delvac 1. The regular Delvac is ordinary dino oil and would be comparable to Chevron Delo or Shell Rotella. The Delvac 1 is a full synthetic that I would use if I could find it. In some parts of the country it is very rare and very expensive at $6 to $8 per quart.

If you're having someone else, such as an MB dealer, do your oil changes, you might want to check on what they're putting in your engine. Just two weeks ago, my dealer put in Castrol GTX 10W-40 in my engine, and that oil is not Diesel rated. I've also heard of several other dealers putting the wrong oil in Diesel engines. So don't just assume that they know what they're doing!

I have forgetten the exact specifics, but for an oil to have a certain S rating, by definition it has an equivelant C rating, even though it is not marked that way on the container. For example (again, I am going off dim recollection so this may not be exactly correct) for example, say an oil had an SF rating a few years ago. The mil-spec that is equivelant to SF also has a spec which is equivelant to say, CC or CD. Therefore by extension, there is virtualy no motor oil (except for non-detergent of course) which you can purchase in North America which is unsuitable for use in light duty diesel engines. Please note that I am not suggesting that you run some generic 10w40 in your brand new diesel, I am just stating that any oil rated higher than about SF or so is suitable for light duty diesel applications, even though it may not necessarily be the best choice for such applications. This info can be found in an old Frank King article in MBCA STAR Magazine from about the mid to late 80's if somebody would want to take the time to locate it.

Rick Miley wrote:

"Those of you using Mobil 1 oil in your Diesel engines, please check the ratings. That oil is not rated for Diesel engines and Mobil does not recommend it."

Rick-That is not true. I have been using Mobil 1 for years in my engines. It is, in fact, rated for diesel applications - CF. You can view the data sheet at the following link:

http://dallnd6.dal.mobil.com/GIS/MobilPDS.nsf/26b7c4b33367a4a086256665004e4266/9337c5cedcf5e32e852567b60056db77?OpenDocument

I use Mobil 1 as opposed to Delvac 1 because my engine (OM603.96) is indirect injection, while yours is direct. With indirect injected engines, soot accumulation and oil contamination will develop at ~5000 miles REGARLESS of oil type. Thus, it is a simple matter of cost.

A couple of points. I own a '98 E300 turbodiesel, the
same as Rick (or is his a '99, can't remember).

The owners manual/maintenance manual states that an
oil meeting CG-4 is required by this engine. Mobil 1
*does not* carry such a rating - it is CF rated, which
is two generations back in the rating system. The
assumption that a CF rated oil is sufficient for all
light duty diesel engines is incorrect - it does not
meet specifications for the OM606.96 engine, and could
therefore void the warranty.

Delvac 1 does carry the CG-4 rating, and is therefore
an appropriate choice for the OM606.96 engine. It is
available at Mobil distributors - look in the yellow
pages under "lubricants." I purchased a large supply
for about $18/gallon, so it is priced competitively
with other synthetic oils.

The OM606 is not a direct injection engine. It is the
last of the indirect injection diesels. The CDI engines
which have yet to be imported to North America are MBs
first direct injection engines for passenger cars.

Got a letter direct form MB stating unequivocally that they, after much testing, recommend Mobil 1 for 98 and newer Diesels, they also mentioned some other synthetic brands as acceptable too. They now recommend ONLY synthetic oil.

Believe Ye This...
 

http://www.api.org/programs_services/quality/oilchart.htm

That was a link to the American Petroleum Institute website, leading to their "oil chart".

Some of you are right, and some of you are, well, almost right.

Mercedes should revise their literature, as a CF rated oil is not designed for use in direct injection diesel engines. Mobil 1 has a CF rating. In my 1982 300SD, it would work great, but in a newer diesel with direct injection you need a CG-4 or even a CH-4 rated oil. DelVac or DelVac 1, DELO 400 or Rotella T may meet your requirements.

API says: "S category oils are suitable for gasoline engines and C category oils are suitable for diesel engines." PERIOD. there are no equivalencies.

And Castrol GTX is not rated by Castrol for use in diesel engines. Go to: http://www.castrolusa.com/default.asp

OK, this is starting to get interesting...
 

palangi - yep, I know that. My post was based on a phone call to Mobil when they told me specifically that Mobil 1 was not designed for Diesel engines and that I should use Delvac or Delvac 1 instead.

goldenbear - thanks for the link to the data sheet. At the time I investigated this the Tri-Synthetic formula was still new and maybe all the ratings were not in yet. Good to know that it carries a CF rating, but that's still not enough for the OM606.

jcyuhn - right on. We have the last of the prechamber Diesels. The only place in Tampa where I could find Delvac 1 wanted $125 for a case of 4 gallons. $62.50 per oil change plus the filter - ouch!

richard u - I have the same letter. However, I'm inclined to believe Mobil (see above) and Mercedes when they said the engine required oil with a CG-4 rating, which Mobil 1 doesn't have. Please notice that the letter says nothing specifically about Diesels. The booklet enclosed with the letter also recommends Valvoline and Castrol oils that do not carry a CG-4 rating. The box on the left side of the page specifically lists Diesels and gives a CF-4 or CG-4 rating. Considering the very long oil change intervals (I'm getting 12,000+ miles!) recomended by FSS, the OM606 should get the best oil you can possibly find.

Oh, and just for the record, I'm changing my fully synthetic CG-4 rated oil twice as often as recomended by FSS.


The point of all this was to make people really think about the products they're using to maintain these fine automobiles, rather than just assume that something is "good enough". I'm not trying to win a p'ing contest, just promote a healthy exchange of information. Thanks for your replies.

As I understand it the CG4 and CH4 ratings are a result of oil compatibility with GM 6.2/6.5 liter diesels. These engines are equiped with roller lifters whose needle bearings are known to fail prematurely due to wear from soot particles. The CG4 and later CH4 ratings specifically refer to additives that control soot "clumping" and keep it in suspension within the oil. These engines require this rating on the oil and not using it is asking for faliure. Now this may or may not apply to MB diesels but it would seem that keeping the soot as controlled and inert as possible would be a benefit? Your results may vary but I would think using a diesel rated oil a bare minimum in any diesel engine. RT

Rick -

I paid about $68 per case of four gallons for Delvac 1
at a local Mobil distributor. Mobil has an 800 number
you can use to locate all the Tampa area distributors
of Delvac 1. Perhaps there are several, and one will
have reasonable pricing? Failing that, you could mail
order it much cheaper than $125/case, even though
shipping would still be a bit expensive.

- Jim

I was checking out Mobil 1 synthetic ATF last night at Pep Boys at $5.99 a quart (I didn't buy any). Any thoughts on how it compares to Redline ATF's? I've had some hard shifting problems, and my tranny is slow to shift from R to D or D to R. Right now I'm running Esso Dexron-??? ATF which was dirt cheap at $9.99 for a case of 12 quarts.

Rick
This was a good discussion, and I enjoyed it. Thanks for starting it. It's always interesting to see the different viewpoints, even though we don't always agree 100%. I looked at a Mobil 1 container today. It is marked SJ/CF. If I remember CF correctly, it is for light duty turbocharged diesel. Plenty good at least for the older diesels. When we are talking about the new diesels of the last few years, I think we now have 2 distinct requirements. First, we want to lubricate the engine (and suspend contaminants). Second, we want to keep the FSS system happy happy. FSS system is ahead of it's time. MB made a big mistake by not specifying synthetic oil in FSS engines from day one. The superiority of synthetic lubricants has been known for more than a decade. Big mistake to introduce FSS while allowing dino oil, especially in gasoline engines. Some of the dino oil couldn't handle the varnish. Best way to fix it was obvious, and should have been so from the beginning... use better oil.
Circumstances on my old 300D are such that I didn't feel it wise to go to full synthetic. The main factors were leaks and cost. I went to semi-synthetic about a year ago ( successful at this point ). I think I will run with that for a while longer and just see how well it does. If I hit the lotto and get a new diesel, I guarantee it will have synthetic oil right from day one, which is the same way I did my new ( in 1991 ) Toyota.
Cheers !

Folks - Save your money and use Shell Rotella T 15W-40 oil or Delo! We all want what is best for our Mercedes but unless you live in the Sahara Desert or Alaska you just are wasting your money on synthetic. The function of oil is to lubricate and suspend trash and particles of soot. For a diesel you need the CH4 rating, or better the Cat TO2 and Cummins CES 20077 rating. These are much higher specs that CH4. Mobile 1 is only rated for passenger car diesels and would never cut it in a big rig. I have had Cat engines go 900,000 miles before teardown and very very little oil related wear with Rotella.

http://images.honesty.com/imagedata/...8/29504843.jpg

1995 S-350 138,000 miles

I Agree, And Disagree...
 

While CH-4 IS the highest current rating for diesel engine lubricating oil, it isn't necessarily the appropriate oil for the older engines. There is nothing wrong with using it, but there is also nothing wrong with using Mobil 1 with it's CF rating. In fact, there are certain advantages...

The benefits of synthetic oil aren't just better lubrication at high temperatures, and easier flow when starting at cold temperatures. There are many more, and not the least of them are: increased fuel economy, no wax or paraffin build up, better detergency, almost no formation of acids from the condensation formed during the combustion process, and better overall lubrication.

I truly believe that the Mercedes Benz passenger car diesel engine with indirect injection will work to it's optimum performance and best longevity with a combination of proper maintenance, high cetane rated fuel and additive, regular oil & filter changes, and the use of a synthetic motor oil with a rating of CF.

The chart at the API website is the best determining factor for choosing motor oil for your passenger car diesel.

http://www.api.org/programs_services/quality/oilchart.htm

Mercedes Benz passenger car diesel engines are about as related to a CAT diesel in a commercial vehicle as a Palomino is to a Zebra.

And if I were still running trucks with CAT and Big Block Cummins engines across North America like I used to, I'd be using Mobil DelVac 1 right now...

Re - I agree and disagree
 

I agree with you that Delvac 1 is superior to Rotella, but for the price difference, what I am saying is that, it is not worth it unless you use oil sampling and increase your change intervals. Most Mercedes owners would not do this and be changing the oil before it needs to be. But still if the price of Mobil 1 and Rotella were identical, I would choose Rotella. If the price of Delvac 1 and Rotella were equal, I would choose Delvac 1.

Hey Rick,

There is a guy named Shag that also started quite a discussion on oil for gas engines too. In that thread I made my case for Castrol, and I'm not going to do that here, but we have ignorantly used GTX and other oils in my 300D for 16yrs.
Albeit, this car has only 100K mi on it, but the thing runs great and does not use any oil between changes nor does it leak! I think the advent of cable modem and last year's purchase of a new ML causes me to spend more time on this site than I'm willing to admit, but I'm learning alot!

So...what have I learned? That Mobil 1 is not the only choice nor the best one, and that diesel rated oil is probably a good thing for my 300D. I agree with oldsouth, pure synthetic is only worth the cost if your climate is extreme or if what you're buying is some amount of piece of mind that you have the best possible (this individual is probably an audiophile too;)) oil product.

But most importantly, experience proves that frequent oil changes, every 3-4K miles or at least three times a year, will do more for your engines longevity, regardless of what it likes to drink, than anything we can agree to disagree on here! :)JMHO:)

Hey Rick,

Do you live in Tampa? If so, where about? Drop me an email. I'm in the south side of the city.

Daniel

Curious about Castrol GTX
 

Greetings All,

I particularly interested in a heavier weight oil going into Summer and several have mentioned Castrol GTX 20W-50 and having a few quarts left over from a Harley I use to own, (should have kept my Baby) I looked at the bottle and it listed it as a multigrade oil suitable for diesel engines. Although after looking all over the place locally for the same thing, the 20W-50 Castrol GTX is only listed as a gasoline engine oil with no rating for diesel use. I'm still curious for an answer to my prayers so I contact Castrol by e-mail and here is their response.


Thank you for your inquiry regarding the proper oil to use in your Mercedes
diesel car.

Just to clarify the change of labeling-- The American Petroleum Institute (API)
Performance
Category CD has become obsolete as of January 1, 1996. Oil marketers can no
longer use the
CD category designation inside the API donut. The test associated with this API
category is no
longer available, and the Industry can no longer measure API CD performance.
Castrol GTX
as well as leading competitors' grades does not meet API CC/CD performance. For
example,
Mercedes Benz for some time has recommended API CH-4, CG-4 diesel rating.
Having said
that, API CH-4, CG-4 oils should be used for Mercedes Benz passenger car
diesels.

Castrol RX Super 15W-40, a mineral based oil, meets API CH-4, CG-4, CF/SJ
performance for
Mercedes Benz. RX Super SAE 15W-40 contains special anti-wear, anti-oxidant,
and
detergent additives that protect and maintain cleanliness, in hot running,
heavy-duty diesel
engines.

Additionally, an alternative in a part synthetic, SYNTEC Blend Truck 15W-40 has
an API CH-4,
CG-4 approval rating. This would certainly be another avenue to consider if you
are looking to
upgrade to part synthetic oil.

Thank you for your interest in Castrol products, we value your patronage.

Susan Howell

So at this point in time I see no 20W-50 in my near oil change. Can anyone recommend a suitable brand that is diesel rated?

Thanks,

Charles

Charles,

If you are cost concsious and a Walmart guy, sounds like Rotella is a popular choice. If you are a Costco guy like me, you may want to lean toward Chevron Delo.
Check all the other oil polls in this forum...

Neither Offer 20W-50
 

Greetings,

I am a Wal-Mart Guy and yes both brands, actually all three top brands mentioned are offered by them, but I was wanting to switch for Summer use to a 20W-50 that is diesel rated, and have found none available. I guess if I can't find it, I'll just keep running the delo 400 15W-40 in her. Just looking for the added 10W for Summer use.


Charles

20W-50
 

Hmmm, this is an interesting question. can-do wants a 20W-50 mineral oil and we already know Castrol is out of the picture (btw, thanks for the quote). So, I checked some web sites and here's what I found:

Mobil Delvac 1300 Super - no
Chevron Delo 400 - no
Shell Rotella - site was down, but probably no as well
Valvoline - no

The only product I found with a Diesel rating (CF) and 20W-50 weight was Valvoline's Dura-Blend semi-synthetic. Now, good luck finding it. Any other ideas out there?

Rick
You might try looking up a wholesale oil distributor. Sometimes it takes a few phone calls, but I have had pretty good luck locating obscure lubricant products that way.

Is it a safe assumption
 

Greetings Oil Burners,

I know there are many diesel owners out there using Castrol against their better judgement, Castrol's that is. I guess it is safe to assume that a 40W oil is plenty heavy for Summer heat in a heat producing engine. I'd say if it wasn't, Mercedes would have their name on a 20W-50 out there somewhere, wouldn't you say? If you find an oil that if readily available to the consumers that is diesel rated in a 50W, let me know. I'm still curious. Looking into my official MB owner's manual under recommended oils, is shows SAE grades for the current temp range I will be running in to include 20W-50, 20W-40, 30W. I guess there was no soot dispersal added back in 1980 to the oils, so is it O.K. to run a SAE grade? Tell me more. If you have your original manual, tell me what it says.


Charles

Can-Do...
 

I see you have a 1980 TD Wagon, yes? But where do you live, and what are the owner's manual recommendations for oil viscosity for your car?

Boosting viscosity isn't always good for the engine when we measure from the lower figures. We should use the higher numbers, as the lower the viscosity when the engine is "cold" the better flow. I'd stick with a 15W50 over a 20W40.

However, as regards Castrol GTX, I had an extensive conversation with a tech at Castrol the other day about GTX, and it seems that older Mercedes diesels like yours (and mine) would still be able to use GTX despite the new API ratings, as the oil hasn't changed, just the rating.

Longston, is that really your house or I should say estate? Nice.

I Seem To Remember...
 

Seeing your car parked outside of an antebellum mansion with the "stars & bars" hanging off of it...

Was that one yours?

Here's your answer to your question:

http://www.peachparts.com/shopforum/showthread.php?threadid=16554

Just By The Manual
 

Greetings Scott,

The ambiant temp at this point in time through Summer won't be anything under 40 F and the highs will start rising to 86-upper 90's or above. The rated temp range I was looking at in the manual is for anything over 32'F. I'd say honestly that GTX 20W-50 would probably work in these higher temps that will remain constant for the next four to five months. Don't know for sure if there is any advantage to a higher grade except under extreme engine temps, the engine remains lubricated a bit better, but the trade off will be soot dispersal that you gain from a C or CH, or CH-4 rated oil. Is the trade off worth it?


Charles

Yes -- They are both mine or should I say me and my wife. Bought it with the money I saved from using Rotella instead of Delvac 1.

http://images.honesty.com/imagedata/...0/30919066.jpg

1990 copy of D'Evereux

Go Back A few Posts...
 

Look for the two links I have posted for API's chart at their website. An older Mercedes diesel with indirect injection will do just fine with Castrol 20W50. If you want the added benefits of CG-4 or CH-4 rated oil, then use Rotella or DELO 400 15W40, or you could even choose a synthetic 15W50 with a CF rating like Mobil 1. Our local Oil Change GURU, Larry Bible, swears by DELO 400...

Allowing for a high ambient temperature when starting is not an exact factor in selecting motor oil. The ideal motor oil to use in a temperate climate would be a 0W50, as it flows faster and better at start-up. BTW: The Sales Manager for Lubro-Moly, who is located in San Diego, uses their 0W40 synthetic in his Suburban year-round.

The choice of motor oils is highly subjective, and one of the most discussed topics on these forums. Check the archives, ask the manufacturers, go to their websites, and do your homework. I have, and I chose Mobil 1 15W50. Your results may vary...

[Edited by longston on 04-28-2001 at 07:56 PM]

You did mean Delo 400 15W-40 didn't you?
 

Greetings Scott,

You did mean Delo 400 15W-40 didn't you? If they have it in a 15W-50 I'd probably use it in a heartbeat during the Summer.


Charles

Ah Stands Corrected, Sah...
 

Y'all's right, there ain't no 15W50 DELO, only 15W40...:D

I'm sorry about that, but all of these recurrin' oil threads are startin' ta wear me down. Did you know that some of the newer members seem to think that this is a new subject?

But I assure you all, it was going on long before I became a member, and you will see it continue with each new addition to the membership.

What kind of oil should I use?

What's the best oil to use in my diesel?

What does the API rating on the container mean?

Should I use a multi-grade or single grade oil?

Is it better to use synthetic or regular oil?

What viscosity of motor oil should I use?

Should I change grades for summer and winter?

Will using synthetic cause my engine to start leaking?

Can I blend regular motor oil with synthetic?

Is it safe to change to synthetic after using regular motor oil for over 200K miles?

How often should I change my motor oil?

Should I follow FSS, or change my oil sooner?

Will using a synthetic void my warranty?

Why is synthetic so much more expensive?

Should I drain my oil from the pan, or pump it out?

What brand of oil is the best?

What is the best oil filter to use?

Do I need to change my filter every time I change the oil?

Should I change my filter before doing an oil change?


ALL of these questionas have been asked and answered on these forums, and many of them, several times. It's all in the archives...

After a while, the typing finger doesn't move as fast as the brain, and we have a minor error. Thanks for pointing that out, so I could make the correction.

:cool:

I agree with Scott Longston. Wonder if it would be a good idea to put all oil-related threads into their own forum?

I hate to throw more oil on the fire, but Mobil's website says that Mobil 1 is compatible with gasoline and diesel engines a number of times.

I see that Mercedes-Benz recommends Mobil 1 on their newer products, so that's promising.

Also, modern Mobil 1 more than likely exceeds the requirements of the 80s and earlier passenger car diesels.

-Joe

I think if you look at ANY brand synthetic, you will see a "C" rating. Whether or not this oil is up to Mercedes latest standards, I don't know. The newer FSS cars probaly have stricter standards. Oil ratings do become absolete over time. Obviously at some point a CH rated oil will be replaced by CI. This doesn't mean your SOL if your car originally called for CH, because the CI would superceed it.