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-   -   What PSI are you guys running? (http://www.jeepgarage.org/f5/what-psi-are-you-guys-running-21323.html)

babygorilla 04-05-2011 03:19 PM

What PSI are you guys running?
 
Hey everyone,

I'm trying to figure out the optimal PSI in my tires. I have a bit of an offroad setup (265/70/17 Duratracs), and I know a slightly lower PSI is better for off road use. But what about my daily driving? Max on my tire says 50 psi. Can I run 47 or 48 psi? I figure the higher pressure, the better MPG... no?

Crashtown 04-05-2011 03:42 PM

Re: What PSI are you guys running?
 
I'm running 37psi on my BFG All-Terrain E-loads. Disregard the max pressure rating because that for the tire. Specific vehicle rates will vary depending on the GVW. I was accidentally sold a set of E-loads (80psi max) instead of standard C-loads, which are meant for 1-ton trucks. I tried mid 40's for a while, before settling on my current pressure. I may even go a bit lower. I just watch to make sure I'm getting full contact, width-wise.

JonJon 04-05-2011 03:43 PM

Re: What PSI are you guys running?
 
I have my duratracs at 42 psi. It rides well and I didn't see much of any lose in mpg's. I'm curious what I should be running on these too.

babygorilla 04-05-2011 03:48 PM

Re: What PSI are you guys running?
 
Mine are right around 43 now. But sometimes feel as though they are sluggish coasting. Granted... they are beefy as f*ck. haha

JonJon 04-05-2011 04:00 PM

Re: What PSI are you guys running?
 
I originally had mine at 46psi to try to save gas. But after driving through a puddle in the parking lot and onto dry pavement, I noticed that only the center section was really making contact. I don't know if its made a huge difference with 4 psi drop but its better then where it was.

As for the sluggish coasting, you gotta figure they are wider and beefier then stock tires. I noticed that when I let off the gas on the highway that I slow down quickly. I WOULDN'T TRADE THEM FOR ANYTHING THOUGH!!! lol

babygorilla 04-05-2011 04:17 PM

Re: What PSI are you guys running?
 
True that. They are amazing tires. They handled the snow like there was no tomorrow. And they look amazing. No regrets on this one.

Knightrider03m 04-05-2011 06:24 PM

Re: What PSI are you guys running?
 
40 PSI

I was at factory 36 but when I put my tires at 40, my gas mileage went up about a mile per gallon.

jeepgcoman 04-05-2011 08:15 PM

Re: What PSI are you guys running?
 
The quick way to determine the correct pressure is similar to what JonJon said above, check the pattern on the road. Some folks draw a line or lines across the tread (in several places around the tire) with a colored marker or chalk and drive for awhile (straight as much as possible) and recheck to see where it has worn off. If it's worn off all the way across your pressure is about right. If it's worn off just on the center of the tread, you're over pressure, and if on just the outsides you're under pressure.

IMO, the very best way to determine the correct pressure will take several months and/or miles. Most people won't take the time though. I currently run 40 PSI front and 38 PSI rear in my Toyo Proxes tires. What I do is set them at a cold pressure, measure the tread depth all the way across the width with a tread depth gauge. About once a month check them again after verifying that the pressure hasn't changed significantly. If the tread is wearing more in the center it's over and if wearing more on the outsides, it's under. Adjust as needed until a good wear pattern is found.

You can also go out right now, check your pressures, look at the current tire wear pattern, especially if your tires have substantial mileage on them, and see if they're approximately correct, high, or low.

In any case, for on the road driving, you'll find that the factory pressures are usually too low. Of course, off roading will require less pressure. Years ago, when I used to off road alot, I'd run as low as 15 PSI when in sand or loose dirt. Also, as said above, you'll get better economy and tire life when running a higher (correct) pressure.

kkuty 04-06-2011 11:08 AM

Re: What PSI are you guys running?
 
I run my stock tires at 33...simply because that's what it says on the door jam. 33 cold that is. After driving a while, the air expands and ends up settling around 36-38 PSI.

Proper tire inflation is important for proper tread wear. I have 0 experience with over sized tires on my WK...so I can't speak to that.

Megatron 04-06-2011 11:20 AM

Re: What PSI are you guys running?
 
So I should go to 40 then huh? I just have stock tires @ the moment.

paroxysym 04-06-2011 11:37 AM

Re: What PSI are you guys running?
 
i usually run 32-35 psi.. i plan on runing that in my new goodyear silent armors when i get them mounted tomorrow.

Keirik 04-07-2011 02:48 PM

Re: What PSI are you guys running?
 
i run around 36-38 psi cold and that's on the stocker Fortera's that came with my 18" rims on the Overland. They warm up to 40 psi


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