How do you determine a correct tire pressure?

BTW...if there's already been a good thread on this, I'd enjoy being directed to it?

I just swapped my OEM's for 285/75/16 Toyo AT3's and kept them on the OEM rims. My question is, how do I determine the proper tire pressure for commute/highway driving (NOT off-road)? I'm assuming the "max" on the tire is a bit high and the door sticker/owner's manual will no longer apply.

If TP is off, they won't wear properly and performance will suffer. And, they weren't cheap! Thanks for the help!

 

Search for chalk test

 

Look up the chalk test! That should help get your tires within a good range.

https://www.intercotire.com/using_chalk_method_determining_psi

 

Or use tire inflation tables from the manufacturer. I want to say most E tires clock in around the 40s

 

Temperature is best. A contact probe, compare center line temps to the two tread edges in and out. after a few miles of straight running.
If alignment is good, tread temperature will show the regions doing the work.

Check with the racers... they have it down to a science.

 

That chalk test is pretty nifty and, simple. Now I just have to find a neighbor's kid to beat-up and take their chalk!
thanks!

 

https://www.tacomaworld.com/threads/what-psi-should-i-run.51690/

 

Tire pressure is not exact. Pressure will rise one psi for every 13 degrees. Shade and sun make a difference.

 

Heard! I knew about the temperature method but, I'm not going to do hot laps and test with an expensive probe. Even so, I appreciate that input.
Like my friend says, "close enough is, by definition, close enough."

 

except some crews don’t have a clue as to what they’re doing, so they’re hitting the rears with a temp gun and don’t know what any of that means. I’ve went from 5psi at the trailer to 9psi just driving to the staging lanes. Then rising another 2psi just waiting in the staging lanes till I get to the burnout box. I’ll drop my pressure once right before I get into the burnout box. Meanwhile joe blow in his 8 second foxbody and his crew of 6 guys are all clamored around the starting line checking wheelie bar heights and tire temps, doing a rolling burnout past the 60 foot and needing guys to back his car up, just to get eliminated that round by someone who does a normal burnout that doesn’t drag it out past the lights and just checks air pressure and adjusts accordingly.

 

Convert your old tire's load rating and door placard psi to weight; 2,149 lbs.

LTs however, do not need to be de-rated for use on SUVs/trucks...so, 2,149÷1.1=1,954 lbs.

31 psi should get you about 1,962 lbs.

 

I called Toyo and they recommended to not run the tire below 35 psi for on road use. I initially ran 33 then bumped to 35 now I run them at 40psi cold. Seemed like the lower the pressure the less stable the tire was.

 

32-35 psi is always a good starting point unless your hauling a heavier load.

 

The chalk test is from the days of bias ply tires. Not sure how well it works on radials, especially ones with lots of sidewall.

 

I went up to 265/75/16 and use 30 psi summer and 32 psi winter. Works for me, but I don't do highway miles...

Duratracs for the Win!

 

Yep. New radials are way stiffer. I don't think its useful here.

 

Here's how to determine the proper tire pressure based on GAWR and tire size/load rating.

 

That is a nice tool. That site has everything for figuring out the differences when changing tires!