What do you run your 31's at? What do you air down to?

Trying to get a sense of what "normal" is.


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run mine @ 35....have always gotten even tire wear across the tread

never needed to air down

It all depends on the tire(sidewall). With my current set-up I run 28 in the front and 26 in the rear. When I go wheeling I go to @14 front/12 rear.

Depends on the tire.
My gooodyears I run 35
On my mt2's I un 23, anything more and the ride is terrible.

Even tire wear is the goal. I draw chalk lines across the face of the tires and drive for a couple hundred feet, looking to see if the chalk lines are worn evenly.
If the outer edges of the lines are still visible, the tire is overinflated, if the center of the line still present, it's underinflated. I also regularly check the tire wear using a tire depth gauge.
https://www.amazon.com/STEELMAN-978...=2025&creative=165953&creativeASIN=B00GWFOSRS
The ideal pressure is the result of the tire size, rim width and how much weight is on each tire, this number will change from vehicle to vehicle and from trip to trip, depending on the Jeep's cargo load.

When I ran 31"s, the pressure worked out to 30-psi in the front and 28 the rear, with a normal load. off road, they were set at 14-psi
The present 33" X 10.50s run at 28 front and 26 rear, on the street.
Off road, the pressure is dropped to 10-12-psi. This is on regular alloy rims, it could be a lot lower if running bead locks.

I ran a set of 33 X 10.50 KM2s a few summers ago, in Colorado, and found that dropping the air pressure had next to no effect, the tires were so stiff.
Dropping the pressure made the rear end very loose, tending to easily spin the rear end out when on dirt or gravel. The KM2 needed more air pressure to be drivable .
I was happy to sell them and replace with a set of KO2s. YMMV

I run 35 psi in my BFG AT KO2s, when wheeling, I air down to 15 psi. In Moab I aired down to 12 psi without rolling any beads off.

I have BFG K02s also. When running down the highway 35 psi. When I hit the dirt 18 psi. I could go lower but never needed to.

I have been running 36 all around after doing a long road trip.

But really, I need to do the chalk test, like lazyXJ mentioned and drop pressures.

32 on the highway

mine are about 31" now. 30-32 on the road. 12-13 wheeling.

offroad: 14 up front, 12 out back

also depends on your rim width. narrower rims can get away with lower pressure as there some natural pressure from the tire to keep the bead seated. depends on your ply rating as well since 31 are readily available in C rating up to E. I believe I ran the above pressures on C rated tires with a 7.5" wide rim. running 33s now, so trying to remember

I only air down on sand these days. Generous use of the skinny pedal is too fun.

Tire chalk test is the way to go. My STT Pros (load range D) 37x12.5 on a 17x8 wheel need 29psi (cold) on the street to ride "flat". Offroad high speed is ~24-25 and crawling I go down to ~12.