Tires: tire pressure


Question
I own a 2013 Tahoe with P285/45 R22 Bridgestone dueler H/L tires. All info only talks about 20 inch tires and not 22inch tires for proper air pressure.

Answer
DMClark,

The information on inflation pressure - as you found out - is tied to the tire size.  The key to understanding what to do is to understand that you are trying to match both the load carrying capacity or the spring rate - and if you can do both, that's great!

According to Tire Guides, the vehicle tire placard on a 2013 Chevy Tahoe should say a P265/70R17 113S is 30 psi front and rear - or for a P275/55R20 111S is 32 psi front and rear.

Now a P285/45R22 is commonly a 110 load index, so that means about 3 psi more than a 113 LI or 1 psi more than a 111 LI = 33 psi.

Now since that is HIGHER than what is specified for inflation pressure for the OE sizes, you can not use the lower pressure to match spring rates (which is very closely tied to inflation pressure.)