I had a 2000 S500 in the shop today that needed a new valve cover gasket. This is what I found when I pulled the cover. This is, by far, the worst sludged up engine that I have ever come up on.
The only way I know to clean it out would be to do 3000 mile oil changes for a year or so using Mobile 1. Anyone know of another way without taking the engine apart? I suspect that the owner is going by the oil change service indication using conventional motor oil
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