Well I've search high and low for a straight answer and couldn't seem to find one. So here goes it.

How well does a 35 inch tire (specifically a KM2) air down (say 10 psi) on a Cherokee? In other words how well does it flatten out on terrain? Is it enough to make a big difference?

And going off that is the benefit of a bead lock (airing down to 5 psi or so) really so much better than 10 psi?

 

Yes. 10 to 5psi can be a huge difference. Sometimes making an obstacle or not.

Beadlocks are in my future for certain.

km2's need all the help they can get...........

 

Wheel size will make a big difference as well. You can air down a narrower wheel more than a wide wheel. Wheel diameter plays a part as well. With 35s, you can air down a 15 a little more than a 17 and have a less likely chance of popping a bead. I personally haven't ran KM2s, don't care for them, but plenty of people I wheel with do and have and 10psi on a 15x8 and 35s is about as low as I'd go with them.

 

I am driving my sisters '02 Jeep. A couple of days ago a light came on that said BRAKE PI the PI is below the word BRAKE and each is individually circled. I don't find this listed in the owners manual - so can somebody help me with this please?

 

I run 33x10.50x15 Toyo Open Country MT's, they came on the jeep I didnt pick em, and I have to run them at 15 to 18 at least just to get a little sidewall flex. Airing down makes a huge difference in performance for me as well as a more comfy ride on the bumps.

 

I run 35x12.5 r15 KM2s on steel 15x8 rims, running trails, I air down to 10-12 psi, makes for a better ride and much better traction. For snow I air down to 2-8 psi depending on the depth and snow conditions. ( Running 2 psi on non-bead lock rims is very sketchy and you have to watch any side loading. )