Originally Posted by hummerz

I checked the pressures cold and they were @29-30psi. Setting air pressures to 38psi in freezing temps is to high! Bottom line, air pressures set anywhere +30psi, should turn off the warning light, if not, time to replace the TPM sensors.

Originally Posted by Doc Olds

Forget the door sticker. Over the years after the H3 release and in part since TPMS were relatively new to the industry then, John Q Public kept freaking out about getting TPMS alerts/warnings/tire light etc..... TPMS used in the H3 focus on not just pressure, but trigger when one tire is a certain % less than the rest. Also seamed the door jam recommended 32 or 35 was in real life either too weak or the sensors were not functioning properly in the intended range. So the clueless kept taking their under warranty H3s to the dealer because they were too stupid to actually check tire PSI and add air. (I'll bet most auto owners do not even have a tire pressure gauge and much less have an air compressor at home.)

GM figured the way to keep John Q away from the dealers taking up time with false TPMS alarms was to set all four tires being monitored to 38PSI cold. It 100% works. Setting all 4 to the same pressure is important. Example, you could inflate 3 tires to 40PSI, and one to 35PSI, you likely will get a TPMS warning even though all four are fully inflated.

My MTZ 305s are 38PSI around town, and 40 for a road trip, never had issues in either of my H3s.