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I bought a 2nd - 15 Sport Unlimited. It has 35x12.50x18 BF Goodrich KO2 ATs. I called them this morning and they recommend running them at 45 psi - they said 10 more than what the original tires suggest. This still seems a little high... Wanting a smoother everyday road ride.
 

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45 is what a dealer will fill them up to ... I have mine dropped to 33 and it rides much better.

Dealer is just staying that ..
10+ on what the tire side wall says? Wouldn't buy it

Keep it as low as you can before tripping the TPMS!
 

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Lots of factors go into the obtaining the correct tire pressure for a vehicle. As Blue Baby mentioned the chalk test should get you close.

Many people are under the misconception that the pressure on the side of the tire is correct. It's actually a max pressure, not a correct pressure for your vehicle. The same tire on 2 vehicles that weigh different amounts are going to have 2 different contact patches with the pavement at the same pressure. So the tire manufacturers can't stamp a recommended pressure on the tire.

Rim width can also affect how the tread of the tire contacts the road surface. A narrow wheel will pinch the tire more and have a tendency to make the tread pattern curve/bulge instead of laying flat.

The load rating of the tire generally affects the stiffness of the sidewalls which can affect the tire pressure needed to make the correct contact pattern.

Ultimately you want to have the tread pattern laying flat side to side so that it wears evenly. There is a range where it should lay flat on the road surface and you can adjust pressure up or down a bit depending on your preference for a softer ride + more grip for braking and accelerating OR a little harsher ride + a bit better mileage + a little more tread life. Too high of a pressure leads to the center tread wearing out sooner than it should and less contact with the road surface which will increase braking distances. Too low and it will wear in other strange unbalanced ways.

So, ultimately it takes some smart engineers and a bunch of calculating all the factors and testing to arrive at the correct pressure. As soon as you change from the OE tire brand/size you lose all that. Which leaves you doing the chalk test or making guestimates lol

All that being said 45 is probably too high imo.
 

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I bought a 2nd - 15 Sport Unlimited. It has 35x12.50x18 BF Goodrich KO2 ATs. I called them this morning and they recommend running them at 45 psi - they said 10 more than what the original tires suggest. This still seems a little high... Wanting a smoother everyday road ride.
What does it say for the recommended pressure on the sticker on the driver door jam?
 

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What does it say for the recommended pressure on the sticker on the driver door jam?
I doubt it applies to 35's. I thought those were just for factory tires, although I admit i have never looked at it.

I have 35" Mickey Thompson ATZ's. No chalk test(really need to do that) and they run pretty well at 30 PSI.
 

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What does it say for the recommended pressure on the sticker on the driver door jam?
That is only good for factory tires.

Do a chalk test. I found that running my 285/70/17 Duratracs mounted on Pintlers work best at 34lbs cold.

45 is too high. I might push mine up to 40 for a long road trip on dry roads and when I want to max the MPG.
 
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