See also:

Mercedes-Benz M-Class Owners Manual
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Uniform Tire Quality Grading Standards
A uniform standard to grade the quality of tires with regards to tread quality, tire traction and temperature characteristics. Ratings are determined by tire manufacturers using U.S. government ...

Important safety notes
WARNING Follow recommended tire inflation pressures. Do not underinflate tires. Underinflated tires wear excessively and/or unevenly, adversely affect handling and fuel economy, and are more ...