I recently put new tires on my 2001 Montero XLS. However, I went from stock size to 265/75/16 mud tire. Any ideal what air pressure I should run the tires at? Guy who put them on said 50 PSI, I think that may be to much.

 

so you asked a guy who does it for a living.... And you think you know better?

 

It depends on what you are going to do with those tires. For regular daily driving on the paved roads, check the side wall on the tire and see what is the maximum recommended pressure. Make sure to not go over that. My Montero has a sticker on the driver side door pillar with recommended tire pressure for different loads. I found that it is a little too low and I typically run around 40-44 PSI in mine. However, if you plan to get out and drive in the back country soft, mushy dirt and gravel roads, you may want to air down to about 15 PSI. This will improve traction when off road. You will need to put the air back in when you are done and ready to head on to regular roads (you don't want to drive 60 MPH with 15 PSI in your tires).