See also:

Mercedes-Benz M-Class Owners Manual
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Load index
Tire data is vehicle-specific and may deviate from the data in the example. In addition to the load bearing index, load index 1 may be imprinted after the letters that identify speed r ...

Storing the current speed or calling up the last stored speed
WARNING The set speed stored in memory should only be set again if prevailing road conditions and legal speed limits permit. Possible acceleration or deceleration differences arising from r ...