Cold weather tire pressure adjustment

Question

I live in a mild-weather area (typical summer temp about 80F/25C, winter 55F/+15C), but occasionally travel to the mountains where temperatures are below freezing (5F/-15C). The cold temperature causes the tire pressure to drop, sometimes so much that the TPMS warning light goes on. When driving on the highway (even in winter), the tires warm up enough for the warning light to go off again.

Am I supposed to inflate the tires more when traveling to a cold place? My worry is that if I inflate it to 35 psi (my car's recommended pressure) when the car is cold after a freezing night, then the pressure will go way above 35 psi as the car warms up during the day and from highway driving.

Answer 1

You should follow the reccommendations in your owner's manual.

Also available is the tire build decal or "placard", usually located in the driver's door jamb aka "B Pillar", which gives the suggested pressures based on tire size (if applicable) and load.

This pressure is checked/adjusted cold, which means undriven tires in the morning, in the shade. This will work no matter where you do it, and what the morning is like. I would check twice if I was driving from Yuma to Juno, or versa-vice, but I don't think that's what you're asking.

It's kind of self-compensating. Expect highway-driven tires to increase 5-10 psi from where they started, and the tires are designed to handle this change. Granted, coming back I'd maybe stop in Calgary (great food!) and check to see something not amiss, but it probably isn't necessary.

I know my customers (who don't check) always have 24-28 psi tires on a winter oil change, when six months ago I sent them out with 34psi. I reset the pressure to OEM spec and send them on their way.

There's no real problem inflating to the maximum sidewall pressure stipulated on the tire (cold), with the caveats it may affect ride comfort, handling, and tire wear. Add a few extra pounds if you really think you need it, but never exceed sidewall maximum cold.