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What kind of tire pressure should i be running??

Recommended inflation is on the sideway. I am told if you go 2lbs over recommended that is supposed to help out with fuel mileage a little. ;)
 
kyfreeride04 said:
I got a 99 xj on 31x10.50's Big O X/T. What kind of tire pressure should i be running on the road? I want to try an keep the tires from wearing out quickly and hopefully help out on mpg.
Click to expand...

The highest pressure you can run within manufacturer specs will give you the least amount of rolling resistance and thus the best mileage. (as far as the effect the tire pressure would help) Every tire has different ratings.

When I had BFG AT's 31's, I ran my fronts at 40 and rears at 36 to 38. BFG rates the tire to 50 but that would be overinflated.
 
I run my BFG AT/KO's at 40psi cold, they get to about 45 once the do a 60+ mile run down the interstate. Also keep in mind that you need to check the pressure on a somewhat regular basis. The fall/winter temp change generally lowers the pressure about 5-7psi...time to put in the winter air...
 
when i had my 31s i put 40s in the front and 35s in the rear. the mpg were alright but not as much as you think. at least its better than nothing, right?
 
kyfreeride04 said:
I got a 99 xj on 31x10.50's Big O X/T. What kind of tire pressure should i be running on the road? I want to try an keep the tires from wearing out quickly and hopefully help out on mpg.
Click to expand...

i know this is OT but do you have any pics of these tires? how do you like em so far??
 
Go to the manufacturer web site.
Keep in mind that if you have a NP242 that you want the same preasure all around! Otherwise shifting into and out of Full time or Part Time will be a problem.
 
I run 31's and was told that milage isn't the issue, it's tread wear. I run mine 30 psi all around. A guy I know who has jeeped for over 40 years and a master mechanic told me this. I have been running 30 psi for most of the year and the wear on my tires has been min. I also rotate every 500 miles.
FOX
 
I run 28-30 psi in mine. It helped ride quality on my setup, and didn't impact MPG from when I was running 35-40. If you are running at 40psi cold you may want to check them hot too. They shouldn't go up 10psi, but it may be worth checking.
 
I run about 26-28. Any higher and they ride like a brick. I did the patch test and it worked out to 25. I get good even wear.
 
I discovered mine were at 20-22 today. I filled them to 38, and the howling noise that I've been worrying about and posting questions about bearings for the past couple months got significantly quieter.

Since the noise didn't change when driving over different surfaces (e.g. asphalt to concrete bridge), I decided that I didn't need to bother to check the tires. Oops.
 
DementedXJ said:
i know this is OT but do you have any pics of these tires? how do you like em so far??
Click to expand...

The tires have been really nice so far. I've had them for about a year now and they've been awesome. They came with a life time warranty, which was free rotation, free tire repairs (nail in tire, ect..), and free replacement for blow-out. I wanted something with a little more beef than an A/T but not as much as a M/T an these are right inbetween and are perfect.
 
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