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Whats your tire pressure???

Dkretden

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33” stock KO2s. I have been running the first 1000 miles at what the door jam plate says..... 37 psi (cold). I like it. Might go down a few pounds next.
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m3lover1

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Run mine 28 cold in the winter now. Did about 20-22 when I went offroading, but trails weren't crazy enough to need lower psi.
 

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37x12.5R17 Cooper STT PRO tires and 27 psi.
Hey Ted, what width is your rims? I'm running 25lbs on mine to get about a 95% chalk tread pattern on the 8.5in width Mopar Slotted Satin Off-road rims.
 

wibornz

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Hey Ted, what width is your rims? I'm running 25lbs on mine to get about a 95% chalk tread pattern on the 8.5in width Mopar Slotted Satin Off-road rims.
I am running a 9 in wide beadlock wheel....ATX Slabs
 

Uhdinator

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Read between the lines when going with the door jamb PSI recommended.

"That number indicates the minimum amount of air pressure needed to support your vehicles maximum load-carrying capacity."

Recommended psi is a compromise of:
Load capacity (safety)
Traction/perfomance
Tire wear
Fuel ecoomy

My 2dr HT max cargo capacity is 700 lbs (4 passengers). I'm usually by myself and at less than 1/2 of max weight capacity. Having wider tires with a road surface contact area larger than stock skinny tires = less weight per square inch on tire surface as its the same weight spread out over a larger area. Kinda like the same idea as if you stacked 24 packs of shingles on your roof in one spot they would crash thru your roof but when you install them and they are spread out over the whole roof area, supporting them requires much less weight bearing capacity per square inch. (or less PSI for your wider and bigger than stock tires)

Vehicles are usually heavier in front than the rear. Mfr PSI recommendation divides vehicle weight + cargo by 4. I used to run 36 front and 30 rear in my Challenger, as I had less weight in the rear and wider rear tires so the front wouldn't flex as much and the rear would not wear in the middle and have more tire on the ground and better traction.

That being said, I run 32x12 tires @ 30 cold/32-33 warm. Its normal for tires to heat up and increase in PSI about 10%. Obviously with summer temps it is about 4 psi, in winter about 2 psi. If your PSI goes up much more than this after driving awhile at highway speeds...........you may be a little under inflated causing the tires to overheat a bit.

If I had stock tires and no cargo I would likely try around 32 cold/35=36 warm.
IMO if you are not loaded down going with 36-37 cold puts you around 40+ warm and is a bit too stiff.
I would rather get a bit more even tire wear and better ride and sacrifice a little mpg. Also having tires stiffer makes the steering a little more twitchy. Too soft is similar and I have found I can tell the difference of being 2-3 psi high or low with my given tire type, brand, and load rating.

Have you ever noticed the majority of worn out tires you see at a tire shop are always worn out in the center more than the edges. As long as you are not getting 5-6 psi increase after driving awhile you are likely fine going with a few psi less than recommended and you will get a little more life from your tires.

I used to drive 18-wheelers. Front steer tires= 110 psi for 12,000 lbs on the front axle. 6000 lbs per tire.
85-90 lbs for 8 drive tires = 4250 lbs per tire and same for 8 trailer tires = 80,000 lbs max load. Driving empty or without a trailer is a whole different ride and rain and snow make it even more of a challenge than fully loaded.
 
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CanAmMick

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Front 28 cold
Rear 26 cold
 

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For the stock BFG KO2 30-32 PSI cold is good.

Currently 38x13.50r17 Milestar Patagonia 26 PSI cold.
 

Uhdinator

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2018 Sahara lifted with 35x12.5R18 K02’s Load range E
Front 28 cold
Rear 26 cold
I think you're the first person I've seen that understands that a vehicle is heavier in the front than the rear and adjusts tire psi accordingly. :like:
 

FitBliss

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25 on my 37's, handle like a dream. 10's or lower off road. Beadlocks :devil:
 
 



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