See also:

Downshifting
Briefly press the selector lever to the left towards D–. or Pull the left-hand steering wheel paddle shifter. The automatic transmission shifts down to the next gear. If you brake the vehic ...

Mercedes-Benz M-Class Owners Manual
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Setting a speed
WARNING Keep in mind that it may take a brief moment until the vehicle has made the necessary adjustments. Increase or decrease the set vehicle speed to a value that the prevailing road condi ...