So I'm trying to figure out a good psi to run in the new tires so they wear even. I have 8 inch wide wheels and the tires are 305's (approx 12 inches wide). Right now I'm running 32 psi (the air pump at gas station was set to 32 psi but for some reason my air gauge says they're at 30 psi). I did the chalk test and the very outer lugs don't seem to be making contact with the ground. The tires are load range D with max psi of 50. The old 285's were also load range D but max psi was 65. I ran those at 34 psi and they wore perfect. What do you guys think?