See also:

Mercedes-Benz M-Class Owners Manual
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Product information
Mercedes-Benz recommends that you use genuine Mercedes-Benz parts, conversion parts and accessories that have been approved for the type of vehicle. Mercedes-Benz tests genuine parts as well as ...

Tachometer
The red band in the tachometer indicates the engine's overrevving range. Do not drive in the overrevving range, as this could damage the engine. The fuel supply is interrupted to protect the ...