Was wondering what PSI most folks put in to the stock tires. I don't tow anything if that matters. They are the original BFG's.

Thanks,

 

Since I have always run tires outside of their normal intended vehicle/application I have always wondered about this.

Recently I had the opportunity to talk with a VERY knowledgeable person who has worked in the industry for ever as an engineer and who is and talks to the experts on a very regular basis.

He has given me the best explanation so far. THe reading on the side of the tire is a cold reading and they expect the tire to increase in pressure to an optimum tire pressure for that tire with a "normal" operation of that tire. The definition of "normal" to all of us will be different.

The maximum tire pressure you want (HOT) before you start doing damage to the tire is 25% greater than the cold pressure.

The perfect tire pressure you want (HOT) while operating the tire is 12-13% greater than the cold pressure.

So, find an "average" use of the tires (commute back and forth to work, tow only on the weekends, race track use) and when you are in the middle of that "average" use of the tires stop, and check the tire pressure. You want it as close to 12.5% above the cold pressure on the tire. Depending on the load and size of the tire you may have to adjust pressure up or down to get closer to that desired "hot" pressure.

Keep in mind that Heat is what kills tires and the best way of knowing how hot they get it by how much pressure they increase from cold to hot.

There are tons of other ideas, measureing the footprint of the tire, checking wear patterns, etc etc, but this has worked the best for me.

Michael

 

Greetings all, I am running E load tires on my Excursion seeing that I tow a TT. Wehn towing i fill all to 75 psi. when not towing i feel the best pressure is 60psi fron and 65 psi rear.

 

I run 60 or 65 psi unloaded also. I run the E rated goodyear wrangler silent armour's