Originally Posted by buckwheat

Once again, MB recommends Mobil 1 0W40. There's a published SB on the issue. Of course you could call MB USA, or any MB dealer and ask and they'll tell you.

Now that you're clear on what's recommended you'll find that in the end, a lot of people will put whatever they want in their motors - with all sorts of justifications. Personally, I simplify my life by using only MB parts, and complying with MB recommendations. Hey, it's a Merc.