I just got some 38.5 x 15.5 x 15 Bias ply Ground Hawgs. Mounted on 15x10 aluminum rims.(No beadlocks) What psi should I run for offroading? It will be mostly mud. The tire sits pretty flat right with 26 psi in it. Should I go down to 20 or lower. They have stiff side walls so they should stand up well. Thanks for your responses. I am used to 35 BFG's which respond very nicely to airing down.