tire pressure question

[NaluTJ00]

I was woundering when u run bigger tires what exactly should the proper inflation be?

[blkTJ]

when? :dunno:

[jeeper89]

what size? what brand? what type? do you have the tires? for full inflations driving on the road... look on the side.. put more info for the answer you want.

[JpPassenger]

It depends on vehicle weight, terrain, tire load rating, # of sidewall plys, speed, and much more. Here's the closest thing to a formula I've found:

A good test to find your best street pressure is to draw a chalk line across the tread. Drive forward a couple hunder feet, and inspect the line. If only the center is worn off, then you would drop pressure, and if only the edges are worn, you need to increase presure. The goal is to find the pressure at which the chalk line wears off evenly. That is your best street pressure.

Next, a good squat for slow crawling or sand, according to Harry Llewyllen (appologies for mangling his name) is where the sidewall height is about 75% of your best street pressure. Beware, if you have a light CJ5 and load range E tires, this may be down in the single digits!

Pulling some numbers out of my @ss for easy math, if your sidewalls are 4" at street pressure, then you want to lower the pressure until the sidewall is only 3" tall.

Or, easier rule of thumb: Offroad, bulge is good. When bulge look like crease, air too low!

When you are just traveling on dirt roads and going fast, letting out air is more for ride comfort. You don't need much bulge in these conditions.

In any event, check your tires often on the trail. If they feel hot to the touch, you need to either slow down or add air.

[NaluTJ00]

thanks for help.