What is the correct air pressure to run in my 35's on stock 18" wheels?

 

I've always had good luck with 40psi.

 

I kind of had the same question, I don't know how much rim diameter plays into proper psi but with my 20's and 35's I found that 42 psi seems about right.

Anyone else have an idea, I do know that with 46 psi it rides like it's on boulders.

 

What load range are the tires? That is the main factor in deciding air pressure to use. Not the size.

 

Load range D

 

If max PSI is 65, I would run them at about 44-46 with a load range D. Naturally keep an eye out for uneven wear and adjust accordingly. If you decide to go lower, I wouldn't go any lower than about 42.

 

my 35x12.5R18 procomps are E- in the summer i run them about 40-45psi- in the winter/mountains, i run them at 35 for better grip on hard-pack/ice, powder

 

That 40-45 is awful low for a load range E, especially if it has a max of 80. That is half the load carrying ability of the tire, which would be well below your GAWR. I ran 50 on my LR Es and got excellent traction and wear. Tires had 40K on the truck when I traded it, and still had tread.