Not all Mobil 1 oils are Gp-III oils, the 0w-40, 5w-20 are a Gp-IV oil.

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91 MB 300D 2.5L Turbo. Her's

05 MB E320 CDI. Mine

I thought the reccomended oil change interval was 12000 miles?

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05 crd sport - 110000 mi
one torque converter/front pump down
two egrs replaced
one rear control arm, sort of

http://www.jakemooremd.com .
http://www.coastalbendeye.com.

Stop all this oil talk. You are making my hair hurt.

Learn a new thing every day. Oldnavy, are those two grades CJ-4 rated?

Cheers,
Duey

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2K9 Space Grey 335d Sport
2K1 Galaxy Blue Jetta TDI 5-sp

5w-40 is CI-4, CH-4, CG-4, CF-4 and CF,
0w-40 is SM, SL, SJ, EC, CF
5w-20 is SM/CF

The 0w-40 has a higer film strength then the other two oils, but does not have the soot handling abilities of the 5w-40 oil. That said it should do as well as the 5w-40 if ULSD fuel is used and the soot load is redused enough through its useage. That is what I am hoping to find out this year by oil testing now that I have the ULSD fuel. I would love to be able to have both vehicles on the same oil just for ease of shelf storage in the garage.

The 5w-20 would be ok to use in colder climates with more frequent change out periods, the problem being is soot handling abilities would not be very good requiring 3000 to 5000 mile oil changes. I would not use it unless I had to for some reason.

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91 MB 300D 2.5L Turbo. Her's

05 MB E320 CDI. Mine

Hi, I do not understand how 0w-40 Mobil 1 has higher film strength than 5w-40 mobil1.
Both oils meet the high temperature viscosity requirement of greater than or equal to 3.5.

My understanding is Mobil 1 0w-40 is formulated for the wear requirements primarily of gas engines and the cam loads of certain diesels.

The 5w-40 Mobil 1 is formulated to meet the more stringent E series of protocols required for ACEA E-3,4,5 and 7.

I feel that 5w-20 in a diesel would be disastrous. The high temperature viscosity requirement of 2.6 would not be able to withstand the bearing loads irregardless of the increased flow rate.

I am not a tribologist and have no empirical evidence on film strength. I am interpreting data from the oil manufacturers and the requirements API and ACEA. Please use only oils recommended by the vehicle manufacturer.

This past weekend I changed the oil in my CRD and used the last of my hord of Rotella That evening the wife and I went to three Wal-Marts before I found any rotella 5-40 It was $15.xx and I bought the last 5 bottles My bad One stock person said as soon as they get it in it dissappears off the shelf To me that would be a sign they should get more

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Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)

A tribologist...Seriously is that actually your job? If so I am guessing by your username that perhaps you are in the military? I am not joking around I actually think it is kinda cool if thats what you do. Its amazing the expertise some of the members here have.

EDIT: wow i really need to slow down and read ALL of the words LOL

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It may be that your only purpose in life is to serve as a warning to others.

06 CRD Sport
Built 5/11/06
Jeep Green
Rocklizard diff cover
V6 Airbox

They both meet high temp requirments as you say, the 5w-40 just barely makes the cut off for that qualification, and 0w-40 surpasses it somewhat higher numbers if I am remember correctly. The 0w-40 is the only Mobil 1 oil in US that meets MB spec's for chain driven DOHC engines due to high temp shear ability, the 5w-40 is not in the list of oils to meet that requirement. That is why I do not use the M-1 5w-40 in my twin row chain driven DOHC MB clone engine in my Dodge. Maybe I will be able to use the 0w-40 in the CRD for 10k mile oil changes in the future due to less soot in the oil from ULSD, but only with oil sample testing will I make that decission.

As for as the 5w-20 use in a diesel, as I said I would not use it except unless nothing else was available and I needed an oil change bad or to top it up if I was low on oil and no diesel oil available. This oil could be used without any problems if you changed it every 3,000 to maybe as much as 5,000 miles if not driven hard, towing trailers, off roading in the desert, or other such hard use. The way our CRD is driven we could use the 5w-20 M-1 and never be the worse for wear if I wanted to change it every three thousand miles, but I don't want the expence and loss time of changing the oil that often. Not to mention I may want to tow something some day for what ever reason.

Let me restate here:
I do not recommend the use of Mobil 1 5w-20 synthetic oil in our CRD over M 1 T&SUV or D 1 5w-40 oil or any other brand of diesel rated oil.

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91 MB 300D 2.5L Turbo. Her's

05 MB E320 CDI. Mine

So, um, you guys lost me. The Rotella-T 5w40 Synthetic is some pretty decent stuff to put in our CRDs at a decent price? I, too, like the Wallie World specials I find on it. Its the only thing I buy at Wal-Mart. I used to go there for Rain-X windshield washer fluid (green in the summer, orange in the winter...), but I finally found that at Advance Auto.

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2006 Liberty Sport CRD

Yes but the normal price is around $15 a gallon at wally world. The old Delvac 1 is better but hard to find and the first and only time I got any it was $25 per gallon. Rotella-T 5-40 has served me well in my last 3 diesels, all egr equipted. Prior to that I used Rotella dino 15-40 on many conventional VW diesels with very good results

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Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)