I'm running Grabber AT2's 265s on my 03 4x4 5.4, and would like to know whats the best psi to run them at, they are load range E and max psi is 80. I'm worried about to over inflating them and wearing out the center of the tire too fast. (happened on my last truck with hwy tires). had them for about 7-8K miles being at about 35-38 psi, been wearing great, but also been getting bad mpg. about 11city and 13 hwy.
not too worried about what will give me the best traction off road, more concerned about tread life, on road performance and mpg.
btw these tires are great off road, just pulled an f250 out of the mud last week that had 35" nittos on it Haha

 

I run 40 psi in my 285's. That has been the happy median for me as far as wear. I know that's not a lot of help. At the Chevy dealership I work at most trucks we put at 35 (which is manufacture specs) in the summer and 38 in the winter. I'd say you're at a good psi. And you're running 10 ply's, don't expect great mpg.

 

If the tread is crowning, = too much air pressure. Yea, you don't want to do that.

You can check that good enough w/big framing square and a 4' level. Make sure total tread width is contacting the road.

 

I ended up bumping the psi up to 50 and got 2 mpg better on hwy. put a level square on it and most of the tire is level except the the shoulders of the tire.

 

I run 50 PSI in the summer and 40 PSI in the winter in my 10 ply's perfect tread wear rotate every 5K with oil change..