survey1

Thoughts on switching from Mobil 1 10W-40 to 0W-40 on M278 4.6L V8 engine in South Florida? Oil change coming up, currently running on 10W-40, want to switch as I can buy 0W-40 in bulk.

Plutoe

Are you sure your engine is a M278 as most W221 have a M273,but what ever you think you have a 0W40 will work as along as it meets 229.5!

alx

0w40 should work just as well. When hot both are 40 oils

belarus27

0w40 is the approved oil
5w30 isnt , unless its a special order to meet MB specs.
im in CA and will be changing my oil this weekend , and will be using 0w40 european formula , but my engine is 5.5 NA .

survey1

Every S550 since the 2012 model year in the US has the M278. I'm 100% sure my car has it.

sinstrex

0w or 10w is the lower value of the oil so doesnt matter if you use 0w or 10w as the 0w would be more beneficial in colder weather. It would be good to play with the higher value of the oil. I live in Dubai and in summers it peaks at around 124 F. A very reputable mechanic recommended me 10w60 but I think it would be too thick so sticking with manufacturer rating.