See also:

Rear-end structure: side members with specifically graduated material thicknesses
Multi-piece side members and a robust, flexible crossmember made from ultra-high-strength steel form the key components of the rear-end structure. The rear side members are continuous, closed box ...

Mercedes-Benz M-Class Owners Manual
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Important safety notes
If a tire pressure monitor system is installed, the vehicle's wheels have sensors that monitor the tire pressures in all four tires. The tire pressure monitor warns you when the pressure drops in ...