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Which tire pressure should you go by when you are planning to fully load the X? The sticker in the door says Max axle weight is .... at 35 PSI. However the tires say Max weight rating is at 44PSI?

If you are plannign to have the X loaded to the limit, what pressure should you be running the tires at? I know for a trailer it's max of the tire so you get the most load. But what about the truck tires?

by the way, they are the stock 265/75/16
 

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Even the stock tires are made to run on our X and also vehicles with a heavier GVWR. If you're loading the X to the max, which without any suspension mods is 900-1000 lbs. over curb weight, you'd still weigh less than the tire is made to carry.

You can check the tire weight rating on BFG's website. I looked: the stock Long Trails and Rugged Trails have a max weight rating of 2365 @35 psi. If the X, loaded, weighs, say 5400 lbs., then that's approx 1350 lbs loaded on each tire on level ground. So the tire can handle the X loaded, plus, even at 35 psi., according to the manufacturer. Even taking into account that tires are not loaded evenly during cornering, braking, and off-camber situations, the 2365 rating is more than enough, unless you're wheeling hard in the rocks, with aftermarket steel all around, and a very heavy load. If you were often in this situation, you'd be upgrading tires anyway.

So no need to max out the tire. Try high 30s with a very heavy load, assuming you mean stuff like camping gear, heavy recovery gear and people. Even with a moderate load I'd go with 35.
 

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This may be somewhat of a physics conundrum, but I was under the impression that despite the load on a given tire, the psi would remain relative.

In other words, the psi might be 35psi, but if you loaded on more weight the psi would increase.

Imagine you've got a resting piston with 0psi. If you place a load on the rod, the psi will increase inside the piston accordingly.

This could be a faulty example though, as a piston doesn't allow for any lateral displacement of air and a tire does since it's made of an elastic compound.

Actually, now that I reread what I just wrote about the piston, it serves as a perfect example of why you would need to increase tire pressure to eliminate a pancaked footprint and bulging sidewalls under increased load.

Yes, I guess I was dropped at birth.
 

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I completely agree, in principle. Just in this case, the load will usually remain moderate enough for the tires to perform well near the recommended psi. And 44 is going to be too high. Recommended psi is good (perhaps not utterly perfect) for a range of weights.
 
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