Your max tire pressure (on the sidewall) has nothing to do with what you should inflate your tires to. It has to do with what the tire is designed to.

Yes, 350 kpa is 51 psi. However, that is irrelevant given your comments about the gas station tire inflator.

Look on the door jamb. You will see a table that lists 220 kpa/32 psi for standard loads, slightly different for different tire sizes and maximum rear axle loads.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
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