Tire pressure (temperature) increase while driving
What is considered an excessive temperature for tires? If I set my tire pressure to 5psi higher than the manufacturer's recommendation, when driving 65mph on a hot day (100+*) the pressure of the rear tires will increase by as much as 30psi (go from 85 to 115psi). At 10 degrees per 2psi increase that's a 150 degree increase in internal tire temperature. Starting at 75* the tires will reach 225* internally! This is true with both the original Goodyear G670RV and new Michelin XRV tires in size 245/70R19.5-F. This seems excessive to me, so I end up running the tires at the max recommended pressure (95psi, or 15psi higher than the chart recommends). This cuts the pressure increase while driving in half, but results in a harsher ride.
I've weighed by coach several times over the years on various truck scales (rear axle always less than 13,000 lbs. with less than 200 lbs. difference side-to-side). I've checked my pressure gauge against 5 other gauges and all were within 1psi of each other. I use a TST TPMS system (interestingly all 10 of the sensors read 3psi lower than all of my gauges at all pressures from 35psi to 115psi.).
Is a 30psi (and corresponding 150*) increase normal and I'm worrying about nothing? The front tires never increase more than 15psi.
I've weighed by coach several times over the years on various truck scales (rear axle always less than 13,000 lbs. with less than 200 lbs. difference side-to-side). I've checked my pressure gauge against 5 other gauges and all were within 1psi of each other. I use a TST TPMS system (interestingly all 10 of the sensors read 3psi lower than all of my gauges at all pressures from 35psi to 115psi.).
Is a 30psi (and corresponding 150*) increase normal and I'm worrying about nothing? The front tires never increase more than 15psi.
