I have a ford diesel pickup and a diesel benz 300 and have used delo 400 in them for years. What do you guys feel about using this oil in my 94 E320. I have been told the oil is fine for gas engines, but have trusted you guys info for years and I am sure some of you know MB's very well.
What do all of you think?
I put a lot of miles on all 3 veh's and it would be nice to only buy one oil.
Thanks , Dan

A lot of guys, me included, are switching our older gasoline engine cars to CI-4 oils because the new SH oil has a less robust additive package, especially the ZDDP anti-wear additive than prior spec spark ignition oil, SL being the immediate predessor.

New engines don't need as much ZDDP because most have "roller everything". The reason for ZDDP reduction is because the phosphorous-based combustion by products of ZDDP are believed to contribute to catalyst degradation, however, if your car has relatively low oil consumption, it will probably not be an issue, and if you keep it "forever" it's cheaper to replace the catalyst than rebuild the engine.

If you look at a typical bottle of CI-4 oil you will probably find SL, too, but not SH because the SH spec limits phosphorous content (ZDDP) to lower levels than required to meet current HD diesel engine wear test requirements.

Duke

Thanks for the answer. Does anyone else know of any reasons not to use Delo 400 15w40?

. . . and have ever since reading about it here on this forum. You might notice slightly reduced MPG with Delo 15W-40; like most diesel formulations, it's kind of thick even at operating temp. I've heard it can be a problem with starting your car in a very cold climate, but apparently it's fine down to 15 degrees F.

'm experimenting, however, with mixing it with some 5W-30 Havoline (from the same company, ChevronTexaco), to thin it out a little. Delo by itself is kind of thick for a 4-cylinder engine, and I'm trying to eke out all the gas mileage I can.

Still, the majority of the oil in my M111 crankcase will be Delo400.

__________________
* *
-- Paul W. (The Benzadmiral)
('03 Buick Park Avenue, charcoal/cream)
Formerly:
'97 C230, smoke silver/parchment; '86 420SEL, anthracite/light grey; '84 280CE (W123), dark blue/palomino

Viscosity has nothing to do with API service category. They are completely independent. The SAE "weights" are based on the oil's viscosity at 0C and 100C. Because higher viscosities are usually specificed for diesel engines compared to spark ignition engines, 15W-40 is the most common multi-viscosity CI-4 grade; 10W-30 is also available, but not commonly stocked in warm climates, and synthetic base CI-4s are available in 5W-40 if you have to do subzero cold starts.

Prior to switching to CI-4, I was using 20W-50 year round.

A 15W-40 is certainly a "year round" oil on the Gulf coast, most of the Southwest and the Pacific Coast.

Duke

I have used Delo 15-40 in my 86 560 SEL(sold at 200K miles) and 1991 300SE (sold at 145K miles) with great results. Good cold (for Oregon) starts. Don Rasmussen MBZ which bills itself as the oldest MBZ USA dealership, used (in the old days before synthetic) Pen 15-40 long distant for all its oil changes both gas and oil burners. This is a similar formation as Delo but in many opinions, not quite as good quality (subjective). Just change it every 3,000 mlles.