What tire pressure do you recommend?

[Weeble]

I just upgraded my tires and noticed the shop inflated them to 40 psi. Or at least that is what they were reading after driving home. The new size is 265 70 17. Should I stick with the manufacturers 33 psi or change it based on the new tire size and type?

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[Jay Dee]

I usually run ~35 ish with the AT4s. Kind of preference though.

Whatever you go with though, take your measurements when the tires are cold.

 

[Joestac]

Load on those AT4Ws? That will matter.

I am running 33 on my 265/70/18 AT4Ws, E load. Feels pretty good so far.

 

[127.0.0.1]

so many variables...so it is best if you do some initial investigation
for your tires and your loads

start with chalk test pressures front and rear
then adjust for mpg, handling, suspension as you like

but chalk test pressure is a good starting point to know
also compare door sticker pressure to chalk test pressure

 

[suremang]

Typically you increase tire pressure when swapping from OEM to LT tires for load rating. My Mickey Thompsons are currently at 38 psi cold.

 

[4score]

so many variables...so it is best if you do some initial investigation
for your tires and your loads

start with chalk test pressures front and rear
then adjust for mpg, handling, suspension as you like

but chalk test pressure is a good starting point to know
also compare door sticker pressure to chalk test pressure

For those who don't know:


The chalk test is a simple way to see whether your tire pressure is giving you even contact across the tread. The basic idea is: mark the tread with chalk, drive a short straight line, and inspect how the chalk wore off.
How to do it
1. Start with a cold tire pressure setting close to your door sticker or a sensible starting point.
2. Find a flat, smooth area like an empty parking lot or quiet straight street.
3. Draw a thick chalk line across the full width of each tire tread, including the outer edges and center ribs.
4. Drive straight for about 50 to 200 feet, without hard braking or turning.
5. Stop and look at where the chalk rubbed off.
How to read it
• If chalk is rubbed off mostly in the center, pressure is too high.
• If chalk is rubbed off mostly on the edges, pressure is too low.
• If it wears off evenly across the tread, you are close to the right pressure for that tire and load.

 

[RunnerRocks]

Most vehicles have less weight in the rear.

Then why are recommendations (including OEM) usually for the same PSI for both front & rear ??

Also, wouldn't the chalk test indicate that a lower pressure is required in the rear with less weight ??

 

[4score]

Most vehicles have less weight in the rear.

Then why are recommendations (including OEM) usually for the same PSI for both front & rear ??

Also, wouldn't the chalk test indicate that a lower pressure is required in the rear with less weight ??

Many vehicles use the same pressure front and rear because it simplifies ownership, rotation, and service, and because the chosen pressure is a compromise that works across normal driving conditions.
Even if the rear weighs less, the rear still needs enough pressure for stability, heat management, and load-carrying margin, so OEMs usually avoid chasing a perfect front/rear split for every axle load difference.

It is true that a lighter axle could theoretically run less pressure if your only goal were matching contact patch to static weight. But real tire pressure recommendations are not based on static weight alone; they also factor in the tire’s carcass, how the vehicle corners, braking behavior, and how much load the vehicle may carry later.
That is why a simple “rear is lighter, so rear PSI should be lower” rule usually does not hold for street vehicles.

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