Been through tire inflation threads but

ALASKANMADMAN

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Brand new Toyo 37x14.5R15s and have done the short chalk test with just leaving a imprint on pavement as well as the rolling test from 100 to 200 feet and gauging what is left on the tires. Ive done this multiple times on multiple days and whatever the ambient conditions are tge sweet spot is ALLWAYS 20psi. From all the reading I've done and psi tire calculations this just seems low. I have inflated tires at diffrent levels but the rig seems to like the 20psi but worried about heating up and uneven wear while on highway. Thoughts and suggestions greatly appreciated.

Thank you
 
What is your research telling you the pressure should be?
 
Take an infrared thermometer out on some progressively longer rides and see what the data tells you. I'm running 28psi in my 33's, still could use a little less, maybe down to 25, as I still have about 3/4 inch each side of tire not losing the tint from my limestone driveway.
 
Haven't done the chalk test but the load vs tire load capacity math works out to the 20psi neighborhood for my LJ on 35s. When I've researched this I always come up with 25psi as the minimum recommended pressure regardless of tire size or load, so I use 25.
 
Are you starting with higher pressure and working down or lower pressure and working up? Most tires will prese a window of where good contact is. Also I you are at say 25 psi and you show a tiny amount of overinflation that is not the end of the world either.
 
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Are you starting with higher pressure and working down or lower pressure and working up? Most tires will prese a window of where good contact is. Also I you are at say 25 psi and you show a tiny amount of overinflation that is not the end of the world either.

Higher to lower most tests. I did do low up but same results. And yep these toyos are ok if looking over as they tend to have higher center then sides.
 
Haven't done the chalk test but the load vs tire load capacity math works out to the 20psi neighborhood for my LJ on 35s. When I've researched this I always come up with 25psi as the minimum recommended pressure regardless of tire size or load, so I use 25.

Thank you
 
Take an infrared thermometer out on some progressively longer rides and see what the data tells you. I'm running 28psi in my 33's, still could use a little less, maybe down to 25, as I still have about 3/4 inch each side of tire not losing the tint from my limestone driveway.

Im deffinitly trying to do infrared at this point.
 
As would I
Anecdotally, 26psi is about what a 33 would have on a TJ. My 35s are at 25psi. I would expect 37s to be less PSI than that
Anecdotally, 26psi is about what a 33 would have on a TJ. My 35s are at 25psi. I would expect 37s to be less PSI than that.

Anecdotally, 26psi is about what a 33 have on a TJ. My 35s are at 25psi. I would expect 37s to be less PSI than that.

As would I but 20psi seem a tad low but these toyos are pretty ridged. Gonna swing by harbor freight when in town and pick up an infrared unit.
 
My 33s love 25.5-26 psi. Your tires should not be as high as that. I am betting your 37’s will end up at 22’ish psi maximum…
 
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As would I





As would I but 20psi seem a tad low but these toyos are pretty ridged. Gonna swing by harbor freight when in town and pick up an infrared unit.
I run load range C 35x15 on an LJ that is overweight at 25 psi. You probably have a lighter vehicle, more tire, and possibly more rigid sidewalls.
 
On road: tire temps will determine lowest pressure.
Off road: the bead will tell you the lowest pressure.
I run my 32” KOs at 25 hwy, 15 off road and 10 in the dunes. They are LR-E so the side walls are very stiff.