If you are thinking in terms of heavier oils, you are thinking of older engines with larger clearances. New engines run quite fine on 5w20 or whatever is specified. My 2005 300C used the 5w20 oil as well. Never a noticeable consumption of oil between changes, though it was just a baby at 115k miles when I traded it.
Honestly, I've never put high mileage oils in anything so I have no idea what they would help. Even at 200k plus miles, regular oil has always functioned fine.
Honestly, I've never put high mileage oils in anything so I have no idea what they would help. Even at 200k plus miles, regular oil has always functioned fine.