Air pressure for 37s? - : Jeep Wrangler JK Forum
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post #1 of 7 Old 04-05-2015, 05:53 AM Thread Starter
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Air pressure for 37s?

I just put on Goodyear Wrangler 37 12.5 17s on a 14 Wrangler 4 door. The dealer set them at 38psi but a buddy runs his at 28psi, any suggestions?
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post #2 of 7 Old 04-05-2015, 06:04 AM
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Correct tire pressure varies from rig to rig and tire to tire. The weight of the rig, the width of the wheel, and the construction of the tire are all variables. 38 is definitely too much. 28 is probably closer to the correct pressure. The only way to properly set your tire pressure is the chalk method.

Draw a line across the tread of each tire and drive your Jeep forward or backward for a couple of tire revolutions. If the chalk is worn off only in the middle, there is too much air. If it's worn off on the outside, there isn't enough air. If it's worn off evenly, you've found the correct pressure. Write down the number front and rear so you have it when doing tire rotations. Front and rear pressure will often be different as there is more weight on your front tire. Also keep in mind this number might change slightly as your tire breaks in and the sidewalls soften up.


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post #3 of 7 Old 04-05-2015, 07:40 AM Thread Starter
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Thank you for the info, incredibly simple but I would have never thought of it. I am going to do this when I get home from work today. Thanks again.
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post #4 of 7 Old 04-05-2015, 06:45 PM Thread Starter
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I ended up with 28psi in front and 26psi in rear using the chalk method. Thanks for the advice.
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post #5 of 7 Old 04-05-2015, 07:04 PM
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26 works for me. Same tire but a 2 door

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post #6 of 7 Old 04-13-2015, 11:09 AM
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I'm going to guess you are about 10 lbs. too high at 38. What is the maximum allowed psi on your tires? I ask because my 35's upper limit is 35 Lbs. I run 28-29 and also used the chalk test.

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post #7 of 7 Old 07-26-2015, 10:04 AM
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I run 26psi front / 24psi rear same tires, 2 door. When I air down, I'm at 13 front/12 rear
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