You can browse this board and get every conceivable opinion about "the best" oil product for your vehicle, but the most experienced and respected members agree: Use the viscosities and grades referenced in your owner's manual.

If you want your engine to last to a ripe old age, the key lies not so much in the type of oil you choose (within the noted MB parameters), but in the frequency which you change that oil. "In short, change it hot and change it often!" is among the best advice I've ever gotten from this forum. All the rest is commentary...

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Eric

1991 560SEL-Euro (214,000 miles)
1989 420SEL (Retired from daily use at 325,000 miles; Use as donor vehicle)