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-   -   32 Goodyear KM/R Tire Pressure? (http://www.wranglerforum.com/f282/32-goodyear-km-r-tire-pressure-73672.html)

Lowrollin12 12-28-2010 02:38 PM

32 Goodyear KM/R Tire Pressure?
 
I have had my goodyear Km/R with kevlar tires for about 3,000 miles and I am very happy with them.

I am running 32 psi and I am not sure if it should be a bit lower for tire wear and MPG?

Thanks!

burton160w 12-28-2010 03:53 PM

Everyone will probably say something different, but I'm running 28 psi. Gives it a smoother ride then when I was running 33 psi on 31s.

Try the chalk line test to ensure you're not experiencing uneven wear.

Draw a chalk line across the width of the tire treads. Then drive a few feet and see if the chalk line has worn away evenly. If the edges are worn away more then the center then the tire is underinflated. If the tire is worn in the center more then the edges then the tire is overinflated.

Though, you're probably safe between 28-32psi and everyone will be different.

Jerry Bransford 12-28-2010 06:25 PM

Quote:

Originally Posted by Lowrollin12 (Post 950425)
I have had my goodyear Km/R with kevlar tires for about 3,000 miles and I am very happy with them.

I am running 32 psi and I am not sure if it should be a bit lower for tire wear and MPG?

Thanks!

Without knowing what tire size you are running, it is impossible to give you a recommended tire pressure. What size tire? :)

ESP 12-28-2010 06:40 PM

He said 32" in his post. If your running 32s on your JK then your PSI should be 35-37.

Jerry Bransford 12-28-2010 08:21 PM

I see where he said 32 but I did not see any " with that 32... he said he used 32 psi which does not necessarily mean he is running 32" tires.

And 35-37 psi is way excessive for anything over about 26" when supporting the weight of a Wrangler. If he is running a 32x11.50 tire, 28-29 psi at the most is appropriate. The bigger the tire, the less air pressure it requires. :)

ESP 12-28-2010 08:29 PM

Quote:

Originally Posted by Jerry Bransford (Post 951005)
I see where he said 32 but I did not see any " with that 32... he said he used 32 psi which does not necessarily mean he is running 32" tires.

And 35-37 psi is way excessive for anything over about 26" when supporting the weight of a Wrangler. If he is running a 32x11.50 tire, 28-29 psi at the most is appropriate. The bigger the tire, the less air pressure it requires. :)


32" stock Rubi tires and S Rport wranglers all come from the factory with 37 psi rating on the inner door panel. It is not excessive, it is the correct psi for 32" tires on a JK.

ESP 12-28-2010 08:32 PM

Quote:

Originally Posted by Jerry Bransford (Post 951005)
I see where he said 32 but I did not see any " with that 32... he said he used 32 psi which does not necessarily mean he is running 32" tires.

And 35-37 psi is way excessive for anything over about 26" when supporting the weight of a Wrangler. If he is running a 32x11.50 tire, 28-29 psi at the most is appropriate. The bigger the tire, the less air pressure it requires. :)


32" stock Rubi tires and S Rport wranglers all come from the factory with 37 psi rating on the inner door panel. It is not excessive, it is the correct psi for 32" tires on a JK. As I've already said, if he is running 32" tires on his JK then that is the correct rating. If not, we'll I guess we need more info.

Jerry Bransford 12-28-2010 08:37 PM

Ok, whatever you say but I'll just say I disagree that 37 psi is appropriate for a 32" tire even on a JK. I wasn't even aware 32" tires were a factory size tire on the JK.

But... this isn't the JK forum and and 37 psi is excessive for a 32x11.50x15 tire on a TJ. This is a subject I'm not just repeating what I heard. 30" tires on the TJ require 31-32 psi and the bigger the tire, the lower the air pressure it takes when the vehicle's weight remains the same. That's just how it works. One more "for example"... 35" tires on the TJ require 24-25 psi.

ESP 12-28-2010 09:21 PM

Ugh....I've responded to this post after many others on the JK forum and didn't even notice that this was not one of them. I guess I clicked on it from the main page where the threads from all forums are to the right. We'll...anywho, here is the info for the JKs. Stock come with:

Sport = 225/75/16 or 29.3"
Sport S = 255/75/17 or 32.1"
Sahara = 265/70/18 or 32.6"
Rubicon = 255/75/17 or 32.1"

32" stock tire Jeeps come with 37 psi rating on the door. 29" stock tire Jeeps come with 27 psi rating on the door. The weight of the JK is different from the weight of the TJ.

Weight of stock JK = 3785
Weight of stock TJ = 3092

Jerry Bransford 12-28-2010 09:27 PM

I'm betting you're reading your stickers backwards because, again, with the same weight vehicle, you run LESS air pressure with bigger tires. Not more. The smaller the tire, the more air pressure it requires. Which is why my tiny street tires on my lightweight Bianchi road bike run at 120 psi. Again, that's just how air pressure in tires works.

Jp90Talon 12-28-2010 09:40 PM

Would ths also be due to the JKs having a larger rim diameter thus needing a bit more pressure?

Sport = 225/75/16 or 29.3"
Sport S = 255/75/17 or 32.1"
Sahara = 265/70/18 or 32.6"
Rubicon = 255/75/17 or 32.1"

ESP 12-28-2010 09:46 PM

Quote:

Originally Posted by Jerry Bransford (Post 951093)
I'm betting you're reading your stickers backwards

Uh no.

Quote:

Originally Posted by Jp90Talon (Post 951132)
Would this also be due to the JKs having a larger rim diameter thus needing a bit more pressure


Not sure JP, could be. The body weight difference and wheel diameter might be the biggest reasons.

Lowrollin12 12-29-2010 08:57 AM

Quote:

Originally Posted by Jerry Bransford (Post 951005)
I see where he said 32 but I did not see any " with that 32... he said he used 32 psi which does not necessarily mean he is running 32" tires.

And 35-37 psi is way excessive for anything over about 26" when supporting the weight of a Wrangler. If he is running a 32x11.50 tire, 28-29 psi at the most is appropriate. The bigger the tire, the less air pressure it requires. :)

Thanks Jerry! I was thinking 28 would be a better psi... I forgot the 32"


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