View Full Version : Wheel and Tire FAQS

01-04-2012, 08:31 PM
Here are some frequently asked questions about wheels and tires.

Q: What is the biggest size tire I can fit on my stock Jeep JK Wrangler?
A: The largest tire size that the factory recommends is a 255/75R17 (which comes standard on Rubicon models) or a 32x10.50. However, there are many Jeep JK Wrangler owners who are currently running as big as 285/70R17 or 33x10.50's with little to no rubbing issues.

Q: What is the biggest size tire that I can I fit with a 2.5" Budget Boost?
A: 33" without any problems and 35" tires with only minor rubbing at a full flex. Depending on how wide your tires are, you may experience some rubbing at a full turn especially if you did not install an adjustable front track bar and/or are still running factory wheels which have 6.25" of back spacing.

Q: What is the biggest size tire that I can fit with a 3" lift?
A: 35" tires and depending on what lift kit you have, you may still experience some minor rubbing up front at a full flex and when turning.

Q: What is the biggest size tire that I can fit with a 4" Lift?
A: 37" tires but you will need to trim the rear corner of the rocker pinch seam and you may still experience some minor rubbing at a full flex.

Q: Will 15" Wheels Fit on my JK?
A: Most steel ones will fit without any problems and depending on the thickness of the wheel most aluminum ones will as well. The only thing you really need to make sure is that the wheel clears the brake calipers.

Q:Will 10.50" wide tires fit out 10" wheels
A:Yes one of our members karls10jk is currently running this setup.

Q: What back spacing will I need on my wheels in order to clear 12.50 wide tires?
A: I would recommend that you do not exceed 4.75" of back spacing and even at that, you may still have some minor rubbing up front at a full turn. Also, I would recommend that you do not go any less than 3.75" as anything less would cause your tires to stick out very far past the fender flares. Any back spacing within this range should work out great.

Q: What is backspacing?
A: The distance measuered from the mounting surface of your wheel to the outside edge of the rim - see diagram below.

Q: What are wheel spacers?
A: Wheel spacers are rings measuring 1.25"~1.5" thick, are typically made out of billet aluminum and are designed to be sandwiched in between your Jeep's axles and wheels. By installing wheel spacers, you will effectively reduce the amount of back spacing your wheels have allowing you to install wider than stock tires without having to replace your factory wheels.

Q: Are wheel spacers safe to use or do they cause extra stress on your axle or wheel bearings?
A: High quality wheelspacers, the kind that bolt up to your axle first are no more dangerous or cause any more stress to your axles then would a wheel with less backspacing. Anyone who tries to tell you otherwise doesn't know what they're talking about and I have yet to hear a single good or specific explanation as to exactly how they are worse. Just to be clear, the cheap-o spacers (the kind that you can get at PepBoys and are sandwiched between your wheel and axle using the existing wheel studs) are in fact EXTREMELY DANGEROUS. These cheap-o spacers leave little thread for your lug nuts to hold onto and can fail. DO NOT USE THESE!

Q: On the road, what PSI should I be running in my tires?
A: For optimal comfort and even tire wear. you should not run the recommended PSI listed on the sidewalls of your tires. Typically this will be way too much. On average for a 33" tire, I would recommend that you run your tires at approximately 28-30 PSI. For a 35" tire, I would recommend running approximately 26-28 PSI. For a 37" tire, I would recommend approximately 24-26 PSI.

Q: On the trail, how much should I air my tires down to?
A: Typically, I recommend that people air the tires down to about 10~15 psi.

Q: What are all the factory wheels that are available for the JK?
A:Factory wheel type and sizes listed below:

X Standard
Painted Steel - Size 16 x 7.0

X Optional
Painted Cast-Aluminum - Size 16 x 7.0 (2007)
Painted Cast-Aluminum - Size 17 x 7.5 (2008)

Sahara Standard
Painted Cast-Aluminum - Size 17 x 7.5

Sahara Optional
Painted Cast-Aluminum - Size 18 x 7.5

Rubicon Standard
Machined Cast-Aluminum - Size 17 x 7.5

Backspacing on all factory wheels is 6.25"

Q: What is the bolt pattern for a JK wheel?
A:The bolt pattern on a JK is 5 x 5

Q: Will a 33" tire fit on the factory spare tire mount without causing any warping or damage to the tailgate or mount?
A: You should be just fine with a 33" spare tire especially if the sidewalls of it is making good contact with the rubber isolators on the tailgate. The isolators will help prevent the jiggling of the tire and that is ultimately what will cause you problems down the road.

Q: What size are the lugs nuts used and what socket will I need to remove/install them?
A: The lug nuts you will need are 1/2"-20RH and you will need a 3/4" or 19mm socket to remove/install them.

Q: How many foot pounds should I tighten my lug nuts to?
A: You should tighten your lug nuts to 95 ft. lbs. of torque.

Q: Is there any advantages to running a larger rim size vs. a smaller size?
A: Yes, a larger rim size will reduce tire sidewall flexing and this will provide better handling on pavement. On the trail, less sidewall flex can also help to make your Jeep feel more stable on off camber situations.

Q: Are all rims the same or is there a certain type of rim for offroading?
A: So long as you can mount your tire on it, a rim is pretty much a rim. Some Jeepers prefer to run steel wheels as they are typically much more affordable, are easy to touch up and will bend as oppsed to breaking but, they also tend to be heavier than aluminum. The one thing I would recommend is that you try and get a rim that is about 8" in width. The narrower width will help keep your tires from loosing a bead when aired down for the trail.

Q: How do you determine what size tire will fit what size rim correctly?
A: Typically, most off road tires come in a 12.50" width and for the most part, a 10" wide rim is what you would want. However, unless you are running beadlocks, I would recommend that you select a wheel that is 8" in width or there abouts. When aired down for the trail, the narrower width will help prevent your tires from loosing a bead.

If you see the need for changes or updates please feel free to pm me and i will do them ASAP.

01-04-2012, 08:36 PM
A couple of little pieces of info to add.....

-10.50" wide tires can fit out 10" wheels (pm me if you need proof)
-"sandwich style" spacers are only dangerous if they do not leave enough of the lug stud for the lug nut to adequately engage and fasten the wheel down. I personally use these style of spacers (as well as the high quality ones) on my street racing car with ZERO issues.

01-04-2012, 08:43 PM
No I believe you I will ad it I need to ask Johnny to make theses stickys

01-04-2012, 08:45 PM
No I believe you I will ad it I need to ask Johnny to make theses stickys

Hey stop taking my job.

01-04-2012, 08:50 PM
Thanks for the input Karl I updated it you rock:wootrock:

07-27-2013, 12:50 AM
I have a 2013 Unlimited Sahara. I just installed 325-60-18's with XD Monster wheels with a -12 offset. The suspension is stock/no lift. They rubbed a tiny bit on the front bumper at full lock. I trimmed it up about 1/4 inch and it doesn't rub at all. They stick out about 2 inches past the stock fenders but I think that looks really cool.

07-27-2013, 09:02 AM
Great info thread!

08-22-2013, 04:11 AM
Great Info Nothing About 40s
Im Wondering what Backspacing I Need And Width Of wheel for 40x13.50x17s
& 40x15.50x20s ???

11-15-2014, 09:03 AM
How much trimming will I have to do for 44's on no lift?

11-15-2014, 10:40 AM
I ran 44's and no lift. You just need a 2.5" backspace wheel and some trimming of the air dam!

loud pipes
11-15-2014, 01:27 PM
Great thread. Thank you for taking the time to put this together!

Sent from my iPhone using Tapatalk

01-13-2015, 09:03 AM
I am adding wheels/tires to my 2012 JKU with a 2.5" AEV lift. I am going with 35x12.50x20. I am going to install Fuel Hostage wheels. The -24 is 4.5" backspace and the -12 is 5" backspace. The wheel shop I am thinking about using does not have the -24's but wants to install the -12's and said it will not be a problem. What is your opinion? This goes counter to all the threads I have read.

Uwharrie Jeep
03-04-2015, 10:37 AM
I am new to the forum and have found a lot of great info.

I have a 2011 4door unlimited Sahara with a 2.5 inch lift and have been told that I could run a BFG 275/70R18 on the 18x9 XD Rockstar II's with 30mm offset with no rubbing and the rubber will be inside the fenders...is this correct?

Will the 275/70R18 tires rub?
Will the 18x9 with 30mm offset keep the wheels inside the fender to prevent road grim and rock blowback on the jeep?
How will this look and or opinions?

Thanks guys!

Uwharrie Jeep
05-01-2015, 01:13 PM
I have a 2011 JK with a 2 to 2.5 inch lift. I was told 18x9 with +30 offset was the way to go, but I'm now being told +30 is not and that a 0 offset is what I need. I would like to keep the wheel and tire combo close to under the fenders. What offset is right for this setup? Thanks in advance.

05-01-2015, 01:59 PM
I have a 2011 JK with a 2 to 2.5 inch lift. I was told 18x9 with +30 offset was the way to go, but I'm now being told +30 is not and that a 0 offset is what I need. I would like to keep the wheel and tire combo close to under the fenders. What offset is right for this setup? Thanks in advance.

What size tire are you looking at running? The reason for the change in offset is directly related to the size of the tire for clearance issues when turning.

05-12-2015, 03:29 PM
Your 3.5 year old original post is very informative. Your tire pressure recommendations for street and off road helped confirm numbers I had been questioning even with a chalk test. Been at 29-30 and 15-16 on 35's. This and other threads are leading me to 28 on and 12 off road.