See also:

Mercedes-Benz M-Class Owners Manual
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Important safety notes
WARNING   Grains of sand, particles of dirt and other abrasive materials can enter the brake system. This can lead to excessive wear and unpredictable braking efficiency. After the bra ...

Driving on sand
WARNING   Do not reduce the tire inflation pressure before driving through sand. However, if you do so, remember to correct the tire inflation pressure before continuing your trip. Drivi ...