Typically on U.S. models, air pressure for tires is found under the gas filler door.
The presumption is that all tire pressure measurements are done when the tires are cool, such as first thing in the morning before driving OR less than one mile of driving.
This chart also shows additions to the basic recommended pressure for additional passengers and luggage. Further, it points out adding +4 lbs for sustained high speed driving (above 100 MPH).
Never exceed the tire manufacturer's sidewall max inflation recommendation.
I NEVER rely on service station pressure gauges. I have started using electronic air pressure gauge which I like, especially because it has the "Zeroing" feature. This site sells gauges as does your local MBZ dealer.
For every 10 degrees of ambient temperature your tires will change approximately 1 psi. If you haven't checked your pressures in say three months, you might be astonished what they are set at.
Generally speaking, the higher the tire pressure over the basic recommended pressures, the greater tire life.
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