See also:

Cleaning the paintwork
Scratches, corrosive deposits, areas affected by corrosion and damage caused by inadequate care cannot always be completely repaired. In such cases, visit a qualified specialist workshop, e.g. an ...

Mercedes-Benz M-Class Owners Manual
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Fuel grade
Only refuel with ULTRA-LOW SULFUR DIESEL FUEL (ULSD, 15 ppm SULFUR MAXIMUM). Using other diesel fuels could result in increased wear and damage to the engine and/or exhaust system. Never ...