StormChaser404

Yeah, most Diesels call for straight 30 weight, not sure about Mercedes...

Chris in VA

You'll notice 'Delvac 15-50'. Semi oil. Of course, that's not a car diesel, but thought I'd throw that in there.

rikgus

Do not use single grade oil in a auto diesel. Period.
We have endless debates over in the Mercedes diesel forum about the best oil to use, mostly the diff between synth oil and dino oil. They go on for days, and get pretty heated sometimes. But the one thing we DO all agree on is to use multi-grade oil. Any study anyone has ever come up with to support their claim as to "best oil", has always used multi-grade oils.

StormChaser404

In marine diesels, which are generally converted truck diesels, the only oil that should ever be used is straight weight 30. Also it is very important to make sure you are using an JC rated oil (C is for compression for diesel, S would be spark for gas)...

JeromeS.

I think its also expensive. Ive ran nothing but mobil 1 since I got the car in July. The main reason is because the owner rebuilt the engine and used mobil 1 too. Should I continue using it means how thats all the engine has used and seems to do great with it? Will it "be bad" to go to regular oil? The biggest question i have about using mobil one forever is "Will it really extend engine life?".

rikgus

Ah, yes. By the by, why Do they still use straight grade oil in commercial engines?
I use good 'ol Delo400. Had a friend years ago that worked maintenance for the garbage company and that's all they would use. Lot's of us Benz'ers use it religously. At least, those who don't use synth oil.

Merkin

the pump rod is long gone

CGTBrad

Prolly cuz it's dirt cheap

Xaerran

I am running 15W 50 full synthetic.. and I love it!