See also:

Mercedes-Benz M-Class Owners Manual
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INTERIOR
It's inside the R-Class where some of those previously mentioned quirks start rearing their ugly heads. The R-Class has an electronic gearshift lever on the steering wheel. Putting the car into ...

Cleaning the trailer tow hitch
The ball coupling must be cleaned if it becomes dirty or corroded. Remove rust on the ball of the ball coupling, e.g. with a wire brush. Remove dirt with a clean, lint-free cloth or a brush. A ...