I have a 2012 JK with Mickey Thompson Baja ATZ M/T 325/60/18. I need help in knowing what the correct tire psi would be for normal driving conditions. Also they are filled with nitrogen. Thanks!!!!

 

Everyone on here talks about doing the chalk test and you can search it and I'm sure find instructions. When my 35's were mounted the tire shop put like 45 lbs of air in them, I ended up running them between 28-30 psi for comfort and driveability. I would guess your probably going to be in the same boat in the low 30's. Sorry I can't be more specific.

 

Rub chalk across the tread. back up and down the driveway a few times. Adjust the pressure so the chalk wears evenly. outside wear, not enough air ... inside wear, too much. I’m at 28 psi on 37” Toyos.

 

OK, I'm at a loss... why would you put nitrogen in a Jeep tire?!?! You can't ever air down if you need to?

I thought nitrogen was mostly a race tire thing??? Seems like it would be more trouble than it was worth in a Jeep tire.

I've always ran somewhere between 28-32 psi on just about any Jeep tire I've ever had for my daily driving... it depends on the tires you have. I like the chalk test ideas already given.

 

Nitrogen is used because it doesnt lose pressure as quickly, doesnt oxidize your tires like compressed air. Really just cuts down on the quantity of times you have to add pressure to your tire. If you regularly check your pressure and add when needed, regular compressed air is fine.

Not sure why you would use it if you ever plan on purposely airing down, you'll just lose all that nitrogen you just paid extra for!

 

More than likely because shops recommend it and how much "better" it is so they can make extra money...

 

x2 on the test. I too run 37 MTR at 28 around town and for day trips to/from trail head. For overlands with full gear and 3 people I move up to 30 to handle the extra 500-600 lbs. For reference my JK is A JKUR with about 1,000 lbs of mods, dry weight now 5560 lbs.