When to fill tires?

[B&T RVers]

When is the best time to fill tires with air. I set PSI in my tires after weighing the coach, but the tire weren’t warm. I am noticing the tires add PSI as I drive - especially my front tires. Example my fronts were set at 105. When I start up my monitor says 105, but as I drive and the tires heat up the PSI increases to 115.

is this OK, or should I readjust my PSI in each tire at the end of my drive today?

Thanks in advance.

 

[Neemer]

Check and adjust psi if necessary when the tires are cold, like first thing in the morning. The increase in pressures you noted are normal and expected.

 

[RV Fam65]

There is friction between the air and interior of the tire when in motion, due to the mild deformations of the tire while rotating. Friction causes heat, which increases the pressure of the air in the tire.
Always check and adjust tire pressure before moving, and never exceed the pressures shown in the mfgr’s placards, nor the maximum speed stamped into the sidewall of the tire.

 

[Headhunter]

Set your pressure first thing in the morning when cold, and leave it there. The increase in pressure after driving is absolutely normal. I hope you got your coach weighed BEFORE you adjusted your tire pressure!

HH

 

[AbdRahim]

Check and adjust psi if necessary when the tires are cold, like first thing in the morning. The increase in pressures you noted are normal and expected.

Before the sun comes up. On these really hot days, the sun can really heat up standing tires and cause uneven pressures and temps around the coach. Once you start driving temps and pressures sill even out, if they were all adjusted on a cool day or out of the sun.

 

[TJ&LadyDi]

is this OK, or should I readjust my PSI in each tire at the end of my drive today?

You never want to adjust the pressure on a tire that has just been run on the road. They need to cool overnight. Adjust them first thing in the morning.

Tire engineers set all their specs for cold tires (60 degrees +/- a little) and know that the pressure will rise when the tire is run over the road. It is not unusual for a tire to gain 15-20 psi over the cold pressure. The only pressure number we need to be concerned about is when the tire is cold.

TJ