What oil to put in a 2007 e550
What’s more important is Mercedes 229.5 approval printed on the bottle.
W stands for winter and if you were concerned about particularly cold starting, note the following: MB 229.5 approval means a fully synthetic oil. I looked up Mobil 1 specs, and the cold pour points were identical for 0W, 5W, and 10W oils. (-55 F). With full synthetics, then, the numbers are mostly irrelevant. The relevance of the second number relates mostly to engine design, meaning sizes of internal clearances. Ambient temperatures are irrelevant. 30 is fine for an M273.
Again, it needs to be MB 229.5 (not 229.51 or especially .52, which are diesel oils)
Last edited by lkchris; Dec 11, 2019 at 10:08 PM.
What’s more important is Mercedes 229.5 approval printed on the bottle.
W stands for winter and if you were concerned about particularly cold starting, note the following: MB 229.5 approval means a fully synthetic oil. I looked up Mobil 1 specs, and the cold pour points were identical for 0W, 5W, and 10W oils. (-55 F). With full synthetics, then, the numbers are mostly irrelevant. The relevance of the second number relates mostly to engine design, meaning sizes of internal clearances. Ambient temperatures are irrelevant. 30 is fine for an M273.
Again, it needs to be MB 229.5 (not 229.51 or especially .52, which are diesel oils)
I did my share of engine building in the old days, and so few get the bearing clearances thing. We used to build "loose" engines for the dragstrip and needed 50 sometimes even 60 final weight oils. Tighter tolerances and a lighter viscosity oil is needed. By tolerances, as said, it's the second number (after the W) and not the first. The first might get you started on severely cold days.
The best advice is follow the mfgr's spec as those engineers did the same thing. They specced certain bearing clearances that need a certain weight oil to lubricate properly.






