Air down or not?

[El Cid]

I confess that I personally don't air down as far or as often with my XK as I did with my old LJ.

In the majority of Jeeping conditions the air-down advantage is predominantly about ride (like the above posters noted). My ride is already so much more cushy in the Commander that not airing down results in the same bouncing I got after lowering the LJ. So a lot of times I just don't bother, even though I carry a portable compressor in the rig for quick airing up.

On the other hand, there are Jeeping conditions that simply demand air-down. The clearance loss is minimal, and you get much better traction over rocks as the tire flattens out (and you lose the "bounce-off" and such, too). In those cases, I go down to 20 or so with my 285s. Nicely squishy with little chance of popping the rim.

[NeilSmith]

I aired down on the beach to 25 lbs. I didnt try it without airing down and I did see a bunch of people stuck. i had no problems at all.

[WanderingTs]

Has anyone noticed a difference in tire wear? How about the chances of getting chunks taken out by a sharp spot? Logic seems to tell me that a squishy tire's tread would be less likely to be rigidly pushed into a sharp spot, but more likely to try to "hold" onto a sharp edge of a ledge instead of cleanly rolling off.

Airing down seems like it would make for more exposure to the sidewalls by rolling them outward and closer to the ground?

Airing down for Black Bear Pass in Colorado I ended up with a few chunks missing from my tread. The Chute area was similar to what I do here in CA, and I normally do not lose chunks from my tire treads. These are new tires though, so I don't know if it is the tires or the airing down that is more at fault.

[07JeepXK]

I air down everytime I go off roading. Usually I air down to about 16-18 psi.

[Sal-XK]

well if you have Mt's or AT's something other then street tires they are actually made to be aired down. Thats were the importance of how many ply's your tire's have and such. Maybe discount tires can chime in on the subject.

[Doc in AZ]

terrain, tire and rim selection will dictate the tire pressure you will run.

i am a rock crawler & i run 35 / 12.50 / 15's on a rim that is 8" wide. i typically air down to about 9psi. my buddy that runs bead lock keeps his about 3-5psi. when i had rims that were 10" wide i was having problems with "burping" air from the bead at 12 psi. IMHO a fully inflated tire is more prone to being punctured as it is not going to flex. thing of a fully inflated balloon and how easily they pop, but with it half inflated it is more yielding. for research purposes, go out to your jeep and measure the bumper height front and rear. air it down and measure again. it will be a nominal difference. a tall sidewall like i have (10") will have more flex and will have a larger difference from fully inflated to aired down. but with a larger rim size like 17" and a 32" tire (about 7") will have much less difference.

[bruijr]

IMHO a fully inflated tire is more prone to being punctured as it is not going to flex.

I fully agree on Doc's statement. I have experienced that myself a couple of years ago. We were riding a trail in Big Bend National Park (TX) which was covered with little very sharp rocks. Since I didn't air down I punctured two tires. I ended up plugging the tire with the smallest puncture with the biggest screw I could get off my Grand Cherokee (one in the rear hatch). It worked and got us of the trail to the repair shop within the park. I have to say, it was good learning experience for me. I was just starting offroading and ofcourse had no repair plugs with me and not much experience airing down tires.

For me airing down is essential for traction and preventing puncturing the tires.