Just to comment on something Dsinger said about using a ACEA A3 rated oil. There are only a couple of synthetic oils available in the USA that meet the strict European standard. Mobil 1 15W-50 is the only Mobil 1 that meets this standard. Valvoline Synpower 5W-40 is another. Castrol Syntec 5W-50 also claims to meet this standard, though there has been some debate over whether or not Syntec is a real full synthetic, but that's another subject. No oil, be it "dino" or synthetic that is below xxW-40, meets the A3 standard. Porsches come factory filled with Mobil 1 0W-40. I don't know about the factory fills of the newer Benzes, but I am willing to bet it is at least a xxW-40 oil. Again, because anything thinner does not meet the A3 rating for high performance/extended drain interval oil.

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member