Lots of answers here. I'll offer up my suggestion: a technique to tell specifically for your vehicle how much pressure to keep in your tires.
Get a piece of chalk and draw a line across the tread on each tire. Go for a 5-10 minute drive on pavement and look at the wear, comparing the center of the tread to the outer part.
You want the lines to wear evenly at the center of the tread and on the edges. If the chalk is worn off the center but not the edges, your tire pressure is too high. If the chalk is worn off the edges, the pressure is too low.
Results will vary if you add cargo and heavy accessories (bumper, winch, skid plates, stuff typically added to Jeeps). Also, if most of your driving is with a passenger, have that passenger in the seat when you do the chalk test. If you're usually solo, test solo.
I know people with over-sized tires who run at 24-30 PSI in the front and 22-28 in the rear. The numbers may seem low, but the test never lies. By sticking to this test, they get 40k miles on a set of offroad tires on the highway. Well worth the investment of a piece of chalk. ;o)
what kind of tires? Look on the side of them. They'll have a max pressure. No more than that in them. My 33×12.50×15's are 30lbs max super swapers. I run them at 28lbs all the time. never needed to air down yet.
Your off-road tires are probably not made for on-road driving.
You might be able to drop the pressure a bit to make it to where it isn't just riding on the tops of the knobs, but you still won't have good traction on the pavement.
look on the side of the tire it will say ,then i would put a little less in then its says like Ex. 44psi I would put in 40psi so you have more tration
Open your driver's side door and there will be a sticker in the door jam telling you the proper pressure for each tire. This is for ANY TIRE. It's based on the weight of the vehicle, balance of the vehicle, and for optimum wear for all highway/city driving. Do not go by the psi on the side of the tire except for driving off-road.
That actually depends on what size tires you have. Smaller tires require at least 30psi, but larger tires requires less.