Is It OK To Deflate A Hot Drive Tire On My Truck?

I'd say don't deflate the tire, wait until they're all cold and set them all to the same pressure. A tire set to a lower temp when cold will generate more heat due to excessive sidewall flex compared to a tire set to a higher pressure, that extra heat will increase the pressure in the under inflated tire more than the others. After setting them all to the same cold pressure and running them for the day if you still have one higher than the others then you have something else going on. For example, inside tires get more heat off the brakes than outside tires, so if you've got one inside tire running hotter than the others, you might have a brake or bearing issue on that wheel set. Might want to consider getting a cheap infrared temp gun from Hobo Freight for checking heat, they're also good for checking your brakes for equal adjustment and can be used for determining a cylinder misfire.

To answer your second question, I've always run my tires at maximum cold sidewall pressure, on a light load or empty you could run them lower, but then you'll just have to air them up again next time you run heavy, so not worth the hassle IMO.

 

You'er overthinking everything.

Swift is resposible for your tire pressures. They usually send out there worst mechanic in the bunch (and that is a tough call in the Swift world) to check tire pressures at the terminals. Yet Swift drivers fuss over 5psi on the regular.

5 or 10psi is not going to change a thing. Just make sure they are inflated and don't have cords showing while at a Mega company. That is a nuff of a challenge.

They say don't deflate tires while hot because the excess pressure is often the result of the tire's elevated temperature. Nothing damages the tire, but it is likely to be under inflated when it cools down.

Why would you want a 75psi truck tire? You haul light one day no problem. Next load will be so heavy you have to partially fuel to even look legal. Are you going to spend the time re-inflating 18 truck tires to maximize efficiency or risk a ticket for under inflated tires?

 

Y'all actually check tire pressure?

 

Only if it's flat on more than just the bottom.

 

You running a band trailer for Swift?

What you planning to gain with lower pressures? You think you will feel a ride difference?

Tire rating only drops down around 200 pounds load for 5psi. It is not something that is really tunable for benefit.

All you will see from lower truck tire pressures is more understeer from the steer tires more sway in the corners. Not really a benefit.