I have never seen a tire manufacturer make a suggestion for psi. They have on their sidewall what max pressure and capacity are not what you should run them at. I think it has to do with CAFE standards.

 

When I bought Mickey Thompson MTZ 35"s, there was a sticker on each tire, stating the recommended psi.
I don't remember the exact number, it was around 35~37psi. Much more than the 29~30psi that make the treads sit flat.

 

The spares do have TPMS in them. And keep all tires at 36psi if you want dash light to stay off. I put mine at 36psi and spare at 40. No light yet and tire wear is just fine.

 

The older sensors could not distinguish motion from rest or something like that so the spares would trigger the warning. Smarter sensors came along sometime maybe 2011 or thereabouts.

(if I remember correctly....)

 

it seem like mix opinion on pressure, I am driving on Duratracs and keeping 35psi while sticker is 34psi. Size is stock. Many on another forum strongly suggesting 28-30psi max on Duratracs since they are different type of tires than stocks.

 

28-30psi is plenty on a D or E load tire. You want max mpg run them at 34-35psi. you want traction and comfort run them lower. I read the other forum thread and as much good advise as you got you just refused to use reason. Not sure your motive but good luck in your mission.

 

Here is the deal on tire pressure. You want to run psi that promotes even tread wear across the tread. But you see, that depends on the weight of your vehicle.

Duratracs are D load range tires and can handle up to 65psi. The 34psi recommendation on driver's door of JK is for stock tire which is a B load range tire. Because B load range tire has softer sidewall than D load range tire it sags more at same psi. That's why on D load range tires you would normally run lower psi than what's stated on driver's door sticker.

You can run 35psi on Duratracs mounted on JK which is 5,000lbs vehicle all you want, but you'll be wearing the middle of the tread more than the sides. On the other hand, Duratracs mounted on a heavier truck, like F350 which is 10,000lbs vehicle would require psi higher than that on JK.

 

Very well stated.

 

Agree. With above. I run 33 psi with mine .i have 10 inch wide rims 12.5 wide tires 15 inch rims running 33s .i chalked tires in summer wide sidewalk chalk then drove to check even wear across tread just kept adjusting pressure till even.

 

That seems a little extreme. I looked in the '09 owner's manual and could not find anything related to the TPMS and the tire's max pressure, or coming on with a tolerance of only one pound.

For those interested in the TPMS warning parameters, here is a chart for the JK:

[TABLE="class: MsoNormalTable"]
[TR]
[TD] Placard Pressure (Cold) (PSI)

[/TD]
[TD="width: 278"] Low Pressure ON Threshold (PSI)

[/TD]
[TD="width: 287"] Low Pressure OFF Threshold (PSI)

[/TD]
[/TR]
[TR]
[TD="width: 261"] 28

[/TD]
[TD="width: 278"] 22

[/TD]
[TD="width: 287"] 26

[/TD]
[/TR]
[TR]
[TD="width: 261"] 29

[/TD]
[TD="width: 278"] 23

[/TD]
[TD="width: 287"] 27

[/TD]
[/TR]
[TR]
[TD="width: 261"] 30

[/TD]
[TD="width: 278"] 24

[/TD]
[TD="width: 287"] 28

[/TD]
[/TR]
[TR]
[TD="width: 261"] 31

[/TD]
[TD="width: 278"] 25

[/TD]
[TD="width: 287"] 29

[/TD]
[/TR]
[TR]
[TD="width: 261"] 32

[/TD]
[TD="width: 278"] 25

[/TD]
[TD="width: 287"] 29

[/TD]
[/TR]
[TR]
[TD="width: 261"] 33

[/TD]
[TD="width: 278"] 26

[/TD]
[TD="width: 287"] 30

[/TD]
[/TR]
[TR]
[TD="width: 261"] 34

[/TD]
[TD="width: 278"] 27

[/TD]
[TD="width: 287"] 31

[/TD]
[/TR]
[TR]
[TD="width: 261"] 35

[/TD]
[TD="width: 278"] 28

[/TD]
[TD="width: 287"] 32

[/TD]
[/TR]
[TR]
[TD="width: 261"] 36

[/TD]
[TD="width: 278"] 29

[/TD]
[TD="width: 287"] 33

[/TD]
[/TR]
[TR]
[TD="width: 261"] 37

[/TD]
[TD="width: 278"] 29

[/TD]
[TD="width: 287"] 34

[/TD]
[/TR]
[TR]
[TD="width: 261"] 38

[/TD]
[TD="width: 278"] 30

[/TD]
[TD="width: 287"] 35

[/TD]
[/TR]
[TR]
[TD="width: 261"] 39

[/TD]
[TD="width: 278"] 31

[/TD]
[TD="width: 287"] 36

[/TD]
[/TR]
[TR]
[TD="width: 261"] 40

[/TD]
[TD="width: 278"] 32

[/TD]
[TD="width: 287"] 37

[/TD]
[/TR]
[TR]
[TD="width: 261"] 41

[/TD]
[TD="width: 278"] 33

[/TD]
[TD="width: 287"] 38

[/TD]
[/TR]
[TR]
[TD="width: 261"] 42

[/TD]
[TD="width: 278"] 34

[/TD]
[TD="width: 287"] 39

[/TD]
[/TR]
[TR]
[TD="width: 261"] 43

[/TD]
[TD="width: 278"] 35

[/TD]
[TD="width: 287"] 40

[/TD]
[/TR]
[/TABLE]