Mercedes-Benz 2009 GL320 BlueTEC Operator's Manual page 371

Practical hints
Vehicle status messages in the multifunction display
Do not overinflate tires. Overinflated tires can adversely affect handling and ride comfort, wear unevenly, increase stopping distance, and
result in sudden deflation (blowout) because they are more likely to become punctured or damaged by road debris, potholes etc.
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