I am running 265/70R17 (32's) MT's and I am wondering what PSI I should run. The side wall says that I should run them at 50 PSI but after reading some threads I realized that I should NOT run them that high for the best ride and wear.

Plus, it is about to snow and I am wondering what they should be at for the winter?

 

The 50psi on the sidewall is maximum pressure for that tire.

I run 32 psi in my 295/70R17 Nitto Trail Grapplers all year. The Sidewall reads 80psi maximum.

 

Don't change tire pressure for on road driving. On my 2012 Rubi, the door jam states 37 psi. Seems high for a ~32" tire, but these tires are made specifically for Jeep for the Wrangler. Normally, I'd be running 30-33 psi on 32" tires, but I did the chalk test and 37 psi is perfect, plus you retain your mpg. You only need to deflate if you need to float (sand, deep snow) or traction (rocks, mud) for surface area. Do not air down if you are driving on the road. Period. Keep your tire pressure at your chalk test / factory setting.

 

The 32's are not stock tires. The are yokohama mt's. Thanks for the info though. I need to do a chalk test to be sure.

 

I just purchase a 2012 Rubicon I have stock LT255/75R17 tires on my jeep my question is how much can I deflate my tires without braking the bead on the tire in the snow or rocks.

 

12-16 depending on the tire.

As for the OP, run 32# all year in all my Jeeps on the road. Rain, Snow, Sleet...

 

i like to run 32 on the streets and when i go to the snow i only air down if needed wich isnt very often.

 

I run 32 psi year round, including snow, on my stock Rubi tires and they wear fine. Mine have been siped for the last 30k miles.
I rotate them every 4 or 5k miles.

I will probably replace them in another 4k at 40k miles. If I had behaved better with the go peddle they could easily have went 50k.

Our gravel and clay roads are way too rough to run 37 psi. Would rather not have that harsh ride transmitted to the suspension and steering system. So far the ball joints , etc, are holding up.