See also:

Notes for 4MATIC vehicles
Vehicles with 4MATIC must not be towed with either the front or the rear axle raised, as doing so will damage the transmission. If the vehicle has transmission damage or damage to the front or r ...

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 ...

Additives
Only use DEF in accordance with ISO 22241. Do not use additives with DEF and do not dilute DEF with water. This may destroy the BlueTEC exhaust gas aftertreatment system. ...