No4x4Yet

What are you guys running with bigger tires? I picked my jeep up about a month ago and the tires are alot more worn in the middle. I know bigger tires dont need as much pressure but what should I put em at? They are 31x12.5x15 procomp A/Ts. The valve caps were stuck on when I got the car so I dont know what the pressure was at, but I have them at 28 psi now and they seems to be sitting pretty flat.

Jim_K

My 32's run at 45 PSI

96_xj

read the MAX psi rating on the tire and drop about 5 pounds off that and thats what they should be when cold. But if they are really worn out in the center i might go like 7-10 psi off the MAX rating

Diesel

I had 47 in my 31s

No4x4Yet

I know that max pressure rating is what the tire can handle with out bursting, its nothing to do with what you should run. Cherokees ares fairly light for a truck.

I had 35psi in then and the outer edges of the tires werent on the pavement. On a 300 mile trip i noticed the outside inch or so wasnt contacing the the road and being worn which is why i dropped it down.

Diesel

Factors-temperature, brand, whats in the jeep(weight), altitude.

96_xj

That is always what i have done for my tires and it works well. what size rim are you running? you should have atleast a 8.5" rim if not a 10" rim for 12.5" wide tire That might be your problem

No4x4Yet

The rims are not stock but im not sure of the size. They are fairly wide as the tires fir pretty well.

96_xj

Sick looking jeep! and i am willing to place money that those are indeed a 10" wide rim. hmmmm I say grab some grey paint or marking chalk and run across your thread and play with air pressure till you get the wear pattern you want.


i run my 33's at:
47psi highway
30psi city(no highway really)

Johnny1217

I run 30 psi on my 33's all the time.

No4x4Yet

Thanks. Im a lil worried they may be 10". I cant fit 33s on there and I dunno how wheel a 10" tire will fit.

They tire may be to far gone to save anyway. The old owner said he never rotated the tire in 20k miles. Ill play around with it some more and see what happens. These tires and really any good in the mud anyway and that half the trails around me.

xjmarc

I ran 20 in my 35s and 14 in my 38s and they wore evenly. Both 12.50s on an 8" rim.

troy fritz

I run 32 to 35 in my 31s on the street and 18 to 20 offroad.

xjmarc

Why so much off road? We ran 15 in my brother ZJ on 31s and it was still bouncy. I run 10 in my 35s and ran 12 in my 33s. I've run as low a 6 in the 35s and didn't loose a bead.

Lightfoot

I run on the street 30 psi in my 33/12.50 15 and on the trail I been running 15 but think I will go to 10 to 12 and see how they do.

Nice looking jeep.