Tire Pressure Help

[007]

I'm heading to Ouray with my Ford Expedition (Jeep's not ready yet ). It has stock size 265/70/17 tires.

I run 40lbs in them on the highway, but what kinda pressure should I run on the trails? I don't wanna break down the sidewalls, but I'd like to smooth it out and keep good traction.

I'm going to do Imogene, Brooklyn and Yankee Boy as it stands now.

Thanks in advance...

 

[IOPort51]

Last year I did not air down at all running 31" BFG A/Ts. I think the ride may have been easier if I had but I had no real traction problems. This year I will be running 33" swampers and will more than likely try something like 10 or 12#.

 

[Torxhead]

When I wheel with Wifey's Grand Cherokee, I don't bother to air down and its suspension system seems to handle it just fine, although I do drive it a bit slower. Just be prepared for a possible rock piercing(s) or some thing like that. Carrying at least one full size spare, plug kit, tools, and air. In this pic, I am about 80 miles, 50 of it dirt, to the nearest fix it shop and used the spare after my air pump failed during a patch attempt. I once spent a week around Durango and had a blast with my '96 Grand, they had a great KOA there in Ouray. At one time it had plugs in every tire, sidewall piercings have to get replaced when I get off the trail of course. Oh yeah, and Bilstien shocks help a lot.

 

[007]

Thanks for the feedback. I think I may run about 20lbs. Seems like a happy medium where I can worry less about rocks and won't have to worry about beads or short low speed highway runs to trailheads. That way I can air down when I get there and leave it that way for the week.