Originally Posted by rightyouareken

Strange that yours were that far off. My Longacre analog gauge reads within 1 PSI of the TPMS. All show within 1 PSI of each other when driving as well. However sometimes when the car sits in the sun in certain ways some of the tires may heat up and gain pressure more than the others. Is it possible that’s what happened in your case? Maybe the sun was beating down on that 37 PSI tire and not the others?

Remember also to measure pressure when the tires are cold. They will gain several PSI during driving especially on the highway. Additionally sometimes using a tire pump that gets quite hot may cause some pressure drop in a tire if it was the last one you filled (when the pump got hot filling the others before it) as the air cools back off. I notice this when airing up after off-roading. The pump gets hot and I need to add a bit more air to the 3rd and 4th tire to compensate for the added temp of the air going in through the hot pump. Once the air cools back off those 3rd and 4th tires tend to be a little lower than the first two if I fill to the same PSI.

Sent from my iPhone using Tapatalk