Tire pressure question

[RJEV]

We have a 2008 Allegro 32LA. We've had it weighted and the charts indicate we need 80psi in the rear and 85 in the front. On the safe side we run 85 in the rear and about 90 in the front. We installed Tire Safe and on our last trip we were able to monitor the changing tire pressure.

The temp. was in the 70-75 degree range. The tire pressure rose to 102-105 on the front tires and around 97-100 on the rear.

I know as the tires heat up the pressure rises but I'm not sure how much is a normal increase. Is there a percentage increase that would be an acceptable norm from cold inflation to actual operating temps? I'm a little concerned about what to expect in during the Texas summers when a 100 plus in not unusual.

Thanks,
Robert

[John Hilley]

Tire pressures are always stated cold. I ran into a problem when I came south. I filled my tires to recommended pressure at -5 degrees in North Dakota. When I got to 60 degree temps in Utah, going down the mountain, it started handling funny. When I checked the cold pressure the next morning, it was 15 pounds high, the same amount it was low at -5 degrees. I let the excess pressure out and the handling returned to normal.

[georgetown350]

Manufacturer suggests 90 psi for our tires and Michilen suggests around 80 for the weight we carry.

I set all tires at 90 in the summer and they usually drop into the mid 80s in winter at 20 to 30 degree temps. This way I am never underinflated... might be a little over but I think thats ok. To much of a pain to keep changing pressures when travelling between climates.