Tire Pressure

Sam Spade wrote:

PSW wrote:
By the way, I also carry my infrared temperature gauge with me and I check not only the tires when they are cold and hot, but I also check the temperature of the tires when we stop for gas.

Let's play a little what if:
What if.....you check the temps and one of the inside rear duals is 30 degrees hotter and the pressure is up maybe 5 psi. What will you do about that if there is no obvious sign of a physical problem with the tire ?? Substitute whatever numbers you want, for any one....or two....of the tires.

Higher temps can mean that there is a brake dragging or a bearing going bad but what if you check the rotor temps and the hub temps and they are not much different; then what ??

MANY years ago they stopped putting calibrated gauges on cars and most trucks.....and then went to "idiot lights" because too many "idiots" were seeing a slight change in the gauge and running right to the shop and insisting that something was wrong.....when there usually wasn't.

Sometimes you can be TOO careful.

False premise with the question.
You should only check or set your tire pressure when the tires are "cold". This doesn't mean in the refrigerator but not warmed up by either being the sun in previous 2 hours or driven more than one mile in previous 2 hours.

IR guns are OK for conductive material such as metals but rubber is an insulator so you are not reading the hot part of the tire. Temperatures can vary by 100F within 1/4".

Pressure does not have that problem. Confirm your digital gauge is reasonable accurate (+/- 3 psi or less) from gauges used at your tire dealer.

When cold all tires on an axle should have the same inflation when checked.
Tire inflation changes by about 2% for 10F
Inner duals might normally run a few degrees hotter because of less cooling air flow across the tire sidewall and/or wheel.