Curious because I saw in a recent post that someone was running 45 psi for mileage purposes.

I run 32 psi on 235/75's

 

44 psi because that's what it said on the tire lol
P235/75R15

 

you are supposed to run what the vehicle reccomends. not the maximum pressure as stated on the tire.

with that said. when fitting larger tires sometimes adjustments need to be made for proper wear, ride, handling, etc.

 

And how do you know what that is??

 

says it on the door in most vehicles

 

i run 12 psi in 33s lol

 

Lol, I think the OP was talking about on-rod psi's. For me, I stick to 30psi for my 31's on pavement. Offroad it depends on 2 things - tire width and rim width. If you've got a 12.50 tire on a 8" wide rim, you can go down to about 10psi and not worry about losing a bead on off-camber stuff. If you've got beadlocks though, run the things down to 4psi.

 

Correct, on-road PSI

 

you should be good at 32psi vespa50sp. If you want a little less rolling resistance you can go to 35psi for a cold tire but I wouldn't go past that.

 

stock about 32psi
31's about 28psi
33's about 25psi
36's about 19psi

your jeep is a lot lighter than the truck your oversized tires were designed for, so less pressure will be needed.
too much pressure, and you risk crowning which will result in center tire wear and poor road handling.
too little pressure and you risk cupping of the tires which will result in outter edge tire wear and poor road handling.

there is always the chalk method, where you scrub the chalk across the tire in as much coverage as you can, then drive around the block and inspect where the chalk was rubbed off. adjust tire pressure according to above cupping/crowning.

 

Good numbers to go by. The chalk method works well.

 

lol i know but thats what i run on the street too its my dd lol it rides smooth as glass too

 

And how often do you have to buy new tires?

 

I run with 25 in my 32s. Runs smooth.

 

Hey, lookey there, first post for you! Welcome to CF! I was running 27 in my 31's but started getting some outside wear so I went up.