I just rcvd 4 33x17x12.5 Procomp mt's from 4wheel parts for use on the stock 17" sawblade rims. Once mounted what should I use as "correct" inflation pressure. Sidewall on Procomp's say 50 lbs. ???
Thanx

 

If you look a little closer it sould say "MAX 50 psi" That is the maximum psi to withstand the max load the tire is rated for by the manufacturer. Let's make up a number and say the tire is rated at 2500 lbs @ 50 psi (which is what that means by the way) then that's what you could load that tire up to at that pressure. With four tires, they could handly 10,000 lbs when each tire is inflated to 50 psi. If you have alot less weight than that, you don't need that much pressure to get the same performance from the tire. Usually, (and I say that cautiously because not every case is the same) the sticker in the door will tell you what air pressure to run and that will be a good starting point for any tire on that vehicle. I have 305/70 16's and run 35 psi all the way around. A little firm but the tires seem to be wearing really good and I like the way it drives.

 

I run my front tires at 30 psi and the rears at 32 psi, that is almost the Ford recommended pressures on the door jam sticker.