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chracatoa's avatar
chracatoa
Explorer
Jul 07, 2015

25% increase in tire pressure during the day (above max)

So I had 50 psi on my tires before my trip. 50 is the max indicated on the sidewall. Temperature was around 70F or less.

Later in the day it was around 100F and my TPMS was telling me 62 PSI. This is 25% above the maximum. We made it safely to the campground though.

Is this something I should worry about? How much pressure is too much pressure?
  • donn0128 wrote:
    No. Perfectly normal. Tires are designed for that situation. Sidewall lists max COLD presdure.


    exactly. Gases (air) follow Boyles Law for a constant volume (which a tire basically is) pressure is a linear function of temperature change. And on a hot day internal tire temperature can easily be 120-140F.

    That's why instructions always say to check or inflate tires after they have set for several hours to get to outside temps.
  • No. Perfectly normal. Tires are designed for that situation. Sidewall lists max COLD presdure.