Trailer Tire PSI for Best Traction and Function

Published 03/22/2019

Question:

Can you tell me the proper pressure in psi that my new tires require? The tire says maxload 1075 lbs @ 100 psi. They came with 54 psi in them. 100 psi seems like a lot.

asked by: Chris A

Helpful Expert Reply:

Trailer Tires that have the ST in front of the numbers are special trailer tires designed to be run at their max psi when inflated cold (prior to trip). They will warm up and that psi will actually increase as the friction and ambient temps increase. It may seem like a lot, but under inflation will actually cause premature wear and possible failure as the sidewall of these tires are designed to be firm and under inflating them will make them fail. Under inflating compromises the load capacity and traction on your tires as well.

Most people are used to vehicle tires and the much lower psi and where you aren't supposed to run at the max psi listed on the tire. Trailer tires are very different and designed to be run at their max psi. For instance the # AM1ST77 tires should be inflated to 65 psi which is way higher than any vehicle tire would be run but this is ideal for the performance of this tire.

expert reply by: Jason S