I agree with Peter. High temps and heavy load are critical to keep the engine clean - a clean engine is a happy one.

MB diesels are engineered such that their maximum speed IS their maximum sustainable speed. The governor will not allow the rpms to get to a level that would cause significant damage.

I have similar conversations with inexperienced MB owners who express concern over the engine temp exceeding 100 degrees C. As long as you don't get to the red zone, you are safe - the engine is designed to operate in the broad temp range.

This methodology is very different than other auto manufacturers.

__________________
Chris

'04 ML500 - 53k, Inspiration Edition, Desert Silver
'11 Audi A4 Avant - Brilliant Black
'87 300SDL sold
'99 C280 Sport sold
'85 190E 2.3 sold