JK Wheels 101

[wayoflife]

Okay, I've noticed there's been a lot of confusion regarding the factory JK wheels and it is my hope that this thread will help clear things up a bit:

X Standard
Painted Steel - Size 16 x 7.0

X Optional
Painted Cast-Aluminum - Size 16 x 7.0

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

All the wheels come with a 5x5 bolt patten (5 bolts - 5" apart from each other) and to the best of my knowledge, they will have 6.25" of back spacing with 50.8mm of offset.

As you can see in the diagram below, back spacing is the distance between the Mounting Pad (surface that makes contact with your axle) and the outside edge of your wheel.

http://www.jk-forum.com/uploaded/backspacing.jpg

The offset and back spacing on the factory JK wheels are designed to keep your tires underneath your fender flares and keep you legal in most states. The only problem is, installing wider tires on factory back spaced wheels usually results in the rubbing your tires side walls on suspension components, which as you can imagine is not good. This is why most Jeepers choose to install new wheels with common less back spacing such as 3.75", 4" or sometimes even 4.5". Less back spacing will move wider tires outward and away from any potential rubbing problems.

Can 15" wheels be run on a Jeep JK? I think it all depends on the make of the wheel. Clearly, Full Traction has shown us that 15" wheels fit on their Jeeps but then, they are black steel wheels and things may not work as well with some brands of aluminum wheels.

Another thing to consider is the 7 or 7.5 inch wide wheels. Typically, when installing a 12.50 wide tire, you would use a 10" wide wheel. However, when it comes to off-roading, most people choose to go with 8" wheels in an effort to maintain their tire bead when aired down for the trail. Need I say, 7" is a bit narrow for anything more than 10.50 wide tires and if you're planning to go wider, you may want to consider a set of new wheels.

I hope this helps you out. I'll try to add to this thread if I can think of anything that I might have missed. And, if anyone else would like to add to it, by all means, please do :)

[ericdewayne]

hehe sorry if i caused the wheel monkey to be let out of the bag!

[blkngld]

Quadratec is selling some wheels for the JK. One of them are American Racing FUEL. They are 5x5 with 5" BS and a 25mm offset. To the best of your knowledge, would these clear 35's or would you think I would need spacers if I bought these wheels.

[wayoflife]

Quadratec is selling some wheels for the JK. One of them are American Racing FUEL. They are 5x5 with 5" BS and a 25mm offset. To the best of your knowledge, would these clear 35's or would you think I would need spacers if I bought these wheels.
Actually, according to Quadratec, the wheels have 5.5" of backspacing (which is what TJ wheels have now) but the 25mm offset is about half that of stock. Will they clear 35", sure, but the real question you need to be asking is if they will clear a 12.50" wide tire. And, that would be hard for me to say for sure without doing some kind of test fit or at least taking some measurements.

Man, I sure wish I had my JK in my driveway already so that I can examine things more carefully, whenever I want and as long as I want. :mad:

[Nozz]

3" lift, 35x12.50 on 16x8 wheels, with 4.5 or less backspacing will work? What about the spare tire mount, how big do you think that will hold? Thanks for the help and patients. I was also wondering what kit would be better.

[wayoflife]

3" lift, 35x12.50 on 16x8 wheels, with 4.5 or less backspacing will work? What about the spare tire mount, how big do you think that will hold? Thanks for the help and patients. I was also wondering what kit would be better.

Yes, a 16x8 wheel with 4.5" of BS should work. I have a feeling that we might be able to get away with more BS like 5" or maybe even 5.5" but until I can get a better look at another JK and take some measurments, it's impossible to know for sure. I'll try to stop by Don-A-Vee tomorrow and see what I can find out.

As far as the spare tire mount goes, I have no doubt that it'll hold at least a 33 but anything more than that is probably asking for trouble even if you can physically mount it. The real problem is weight and the ill effects of it on the tire mount and tailgate hinges.

[ejbrokermel]

will i have to buy new bumpers to fit 35" tires with a 3" lift?

[wayoflife]

will i have to buy new bumpers to fit 35" tires with a 3" lift?

I don't think so but I do know that you'll most likely have to trim the plastic air dam or remove it all together.

[bLITZ]

i think new bumpers would be one of my first mods along with a left and tires. Those stock bumpers just don't do it... the stubby rock bumpers in one of the other threads look so amazing.

[luna95]

Not to throw a little more confusion into the calculation, but the stock Sahara wheels (17x7.5, painted) are available as an option on the X package, IF you opt for the S group (which I did, perhaps mistakenly thinking that I'm gonna fit BFG T/As 285/70 17s with a 2" lift...ugh):naw:

(oh yeah, just got word from my father in law that my X is in...unbelieveable; they told me it could be 3 months, and it was barely 3 weeks. I didn't want the car note until I NEEDED 4WD, i.e., snow)

[SpudRacer]

3 weeks?!?! Wow, that's fast!! Does that mean my Unlimited Rubicon will be in next week??

Every time I get a new Jeep, I try to change as much as possible to keep it different from EVERYONE elses Jeep. I already have Orange RUBICON decals for the hood to replace the stock white ones on my black Rubicon. IF I can post a pic here, I'll post what I did on photo shop to change the color of the WRANGLER and UNLIMITED decals on the front lower body.

I like it.

Tom
Bryson CIty, NC

[luna95]

3 weeks?!?! Wow, that's fast!! Does that mean my Unlimited Rubicon will be in next week??



Sorry, but not likely. I'm not sure what they did when they ordered it, but the GM at the dealership I got it from told me that it was line direct to the factory or something like that. Since my father in law is the GM of their sister dealership, I'm getting the hookup basically. Like I said, I didn't want it until next month when the snow hits. Oh well.:rolleyes:

[ericdewayne]

Like I said, I didn't want it until next month

what blasphamy! :naw:

[luna95]

Shoot...you're in TPA. Blasphemy is the (only) FOUR Wrangler Unltds I saw down at Brandon Chrysler Jeep with a big ol' 4x2 on the window sticker. Sheesh. I had to sit and listen to a lady arguing about colors and resale value with her husband as I was ogling the (Jeep's) hardware....I'll be taking mine next week, thank you, snow or no snow. Anyway, back on topic.

[Grant211]

awesome thread! thank God the search engine worked:rotflmao1:

[OCJEEP]

thanks for the clarification eddie :yup:

[nukeman]

Not to throw a little more confusion into the calculation, but the stock Sahara wheels (17x7.5, painted) are available as an option on the X package, IF you opt for the S group


Yep, I bought my '08 X last week and it came with the 17 x 7.5 wheels. It's a shame that I'm swapping them out next week, I actually liked the wheels.

[forumonlooker]

As more posts and any extra information comes in, a revised format of the original post should be stickied.

[BJeepJK]

I hate to revive older threads but I didn't want to start another "will this combo work" thread. So here's what i'm looking at.
I know 33 x 12.5 are tight at full turn/flex so I'm thinking 2-2 1/2" BB w/33's and new wheels. The wheels are where the question comes in, I was looking at the soft 8's but don't want the extra weight so I found these Pro Comp series 8069 the only 5x5 BP they have in 16", as far as I could find, are 16x8 4" B.S. and -11mm offset (the offset is what i'm worried about, most I found are 0 offset and stock is +50.8) ... will this work? not stick out too far?
I found another thread about the ProComp 8069's but they were 17"
Anybody have this set-up? pics? thoughts?

Thanks.

[atomicmecha]

I hate to revive older threads but I didn't want to start another "will this combo work" thread. So here's what i'm looking at.
I know 33 x 12.5 are tight at full turn/flex so I'm thinking 2-2 1/2" BB w/33's and new wheels. The wheels are where the question comes in, I was looking at the soft 8's but don't want the extra weight so I found these Pro Comp series 8069 the only 5x5 BP they have in 16", as far as I could find, are 16x8 4" B.S. and -11mm offset (the offset is what i'm worried about, most I found are 0 offset and stock is +50.8) ... will this work? not stick out too far?
I found another thread about the ProComp 8069's but they were 17"
Anybody have this set-up? pics? thoughts?

Thanks.

you'd be cutting it close with them sticking out or not. There stocks are maybe 2" inside the fender and you are getting wheels with 2.25" less back spacing... so they'd stickout just a little.

[Moetop]

Is this Info in any of the FAQ's.. couldent find it in the wheel and tire, but that was modified section.. Might be a good idea to add it to the FAQ.

[WaIIbanger]

this is embarrassing, but i have never switched wheels except for my YJ, and those were mopars that bolted right on.

why does the whole backspacing/offset thing seem backwards to me? why doesn't adding spacers behind the wheel push the tires out instead of in?

i know i'm an idiot. i'm still figuring out left to loosen. :lame:

[wayoflife]

Is this Info in any of the FAQ's.. couldent find it in the wheel and tire, but that was modified section.. Might be a good idea to add it to the FAQ.

Actually, it is:

http://www.jk-forum.com/showpost.php?p=211274&postcount=3

[wayoflife]

why does the whole backspacing/offset thing seem backwards to me? why doesn't adding spacers behind the wheel push the tires out instead of in?

If you look at the original diagram that I posted...

http://www.jk-forum.com/uploaded/backspacing.jpg

...you can see that reducing the amount of back spacing will bring the mounting pad closer to the axle. This in turn pushes the entire wheel outward. Can you see what I am talking about? Adding wheel spacers effectively do the same thing - reduce the amount of back spacing.

[WaIIbanger]

thanks for the quick reply.

well, let's forget the spacers for a minute and look at your offset. why is it when i look at your diagram, it looks to me as if the tires would be pushed out, not in?

to me, it looks as if the wheel were offset in the opposite direction, then the tire would be pulled in.

i like to think of myself as above average intelligence, but i'm just not getting this.
:thinking:

[wayoflife]

Looking at the diagram, the left side is the inside of your wheel - the side that attaches to your axle. If you reduce the amount of back spacing, the distance between the center line of your wheel and mounting pad will increase. This will effectively move the entire wheel towards the right - outward.

[Moetop]

Actually, it is:

http://www.jk-forum.com/showpost.php?p=211274&postcount=3

Ok I must be really stupid, because I do not see anywhere in that document where it describes the various stock wheel sizes :thinking:

This part of this post.

X Standard
Painted Steel - Size 16 x 7.0

X Optional
Painted Cast-Aluminum - Size 16 x 7.0

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

I dont see it in their

[wayoflife]

Ok I must be really stupid, because I do not see anywhere in that document where it describes the various stock wheel sizes :thinking:

This part of this post.



I dont see it in their

My apologies, you are right and will try to add them in. :embarrased:

[WaIIbanger]

This will effectively move the entire wheel towards the right - outward.

and so how does this bring the tire in?

what i am seeing would be the same as a puck for a body lift. you put the puck on and the body is father from the frame.....not closer.

or like putting washers on a tricycle before putting a rear wheel on.

i appreciate you trying to explain this to me, but i don't want to waste your time. one of my best friends works at a local auto parts store and i will have him give me a lesson on offset/backspacing.

sorry i don't get it. :embarrased:

[wayoflife]

and so how does this bring the tire in?

It wouldn't. I would push the tire out. Less back spacing will give you more clearance between the inside sidewalls of your tires and the frame of your Jeep.

what i am seeing would be the same as a puck for a body lift. you put the puck on and the body is father from the frame.....not closer.

This is correct and I'm starting to think that you have gotten it all along and perhaps there was just a misunderstanding.

i appreciate you trying to explain this to me, but i don't want to waste your time. one of my best friends work at a local auto parts store and i will have him give me a lesson on offset/backspacing.

sorry i don't get it. :embarrased:

LOL!! Actually, I think you do get it. :yup:

[atomicmecha]

and so how does this bring the tire in?

what i am seeing would be the same as a puck for a body lift. you put the puck on and the body is father from the frame.....not closer.

or like putting washers on a tricycle before putting a rear wheel on.

i appreciate you trying to explain this to me, but i don't want to waste your time. one of my best friends work at a local auto parts store and i will have him give me a lesson on offset/backspacing.

sorry i don't get it. :embarrased:

wish i was at home, i could make a little gif animation to explain it. But yeah, wheel spacers are like pucks for a body lift. they push the wheel and tire out, away from the vehicle.

so take the stock backspacing of 6.25" and the wheel is 7.5" wide. so that means that the outside edge of the wheel is sitting 1.25" away from where it bolts to the axle (give or take a few mm ;) ). now, you add a 1.5" wheel spacer, it will push that wheel out, away from the vehicle because its putting a bigger gap between where the wheel bolts to the rotor. so now the backspacing is 4.75 (6.25-1.5=4.75) and now that same 7.5" wide wheel is sitting 2.75" out, or 1.5" futher then before.

the wheel spacers push the wheels away from each other on the same axle is another way to put it.


dunno if any of this helped or not...

[WaIIbanger]

thanks, and by the way....love the site and forum.

i ordered decals from you the other day. no rush...i'm stuck in D status! :)

[WaIIbanger]

dunno if any of this helped or not...

yes it did....thanks to both of you.

[monte]

So if a wheel has less backspacing AND less offset, it will be even further away from the body, creating more clearance for the inside of the tire? For example, the 17" AEV Pintler has a 4.75 backspacing and a +10mm offset; it's then 1 1/2 inches further out PLUS 75mm further out?

[atomicmecha]

So if a wheel has less backspacing AND less offset, it will be even further away from the body, creating more clearance for the inside of the tire? For example, the 17" AEV Pintler has a 4.75 backspacing and a +10mm offset; it's then 1 1/2 inches further out PLUS 75mm further out?


The offset is how far from center the mounting plate is, and then the back space is subtracted from that. so... a +10mm off set would just be subtracting from the back spacing. but not another 75mm, just 10mm or 0.39" giving a total of 4.36" of back spacing. this is how i understand it... but in short, it would bring the tire in a little from what the listed backspacing is. if the backspacing is a negative, it would push the tire out more (minus a negative is a +).


if i'm wrong, someone correct me.



EDIT:::: i was a little off... did some homework and learned something.
ok, the off set is kind of like backspacing, but its more like the difference, hence the name, off set. the to find the off set you take the width of the wheel divided by two so that you get the center line. Now, take the backspacing and minus the center line number and that's your offset in inches. or the the distance between the mounting plate due to backspacing and the centerline.

in otherwords, the off set is the difference in how much backspacing there is and the center of the wheel. so the backspacing pushes the wheel out a certain distance, the offset will be the difference between the middle of the wheel and where the backspacing ends.

so... in an 8" wide wheel, backspacing of 4.75, the off set would be 0.75" or +19mm. keep in mind, the width of the wheel isnt the stated width, its the width between the lips on each side.

now, an 8" wide wheel with 3.75" of backspacing would have an off set of -.25" or -6mm.


so in the first example, the mounting plate of the wheel would be 19mm towards the outside of the vehicle from the center. the backspacing is still 4.75, but its just saying that the plate is now .25" past the center of the wheel towards to outside of the vehicle. in otherwords, the wheel is now .75" off center.

in the 2nd example, the mounting plate would be .25" closer to the frame based on the center of the wheel. so that means that the wheel will be .25" past center going out, so it'll look like the mounting plate is recesed into the wheel past the center.

so if you had a wheel 8" wide and 4" of backspacing, the offset would be 0 meaning the mounting plate is dead center.


so for your question on the off set of +10mm, with backspacing of 4.75, it means that the mount plate is 10mm outside the center of the wheel. but regardless, the offset will not affect the backspacing making it more or less.


i think i got it right now... EDIT::sorry i keep changing this, i keep finding mistakes in my typing.

[monte]

Got it. Besides rubbing, are there any other advantages to having the rim/tire further out from the body?

Is there a minimum backspacing/offset to be able to run 35x12.5 tires without using a spacer?

[atomicmecha]

Got it. Besides rubbing, are there any other advantages to having the rim/tire further out from the body?

Is there a minimum backspacing/offset to be able to run 35x12.5 tires without using a spacer?

a wider track gives you more stability. and it'll allow for wider tires which also help in stability and give you more grip, epscially in sand and mud.

as to backspacing, i think its 4.5 or something close to that... someone else will have to answer that one.

[CHARLIE O]

First let me apologize for the lack of off road education, which I will remedy when I get my jk.

I am looking at putting on 33 x 10.5 on and know that the wider tires will give more traction. Because it will mostly be a daily driver I will probly not go over a 10.5 width. I know as previously explained that the smaller diameter ie. 15"s will be less expensive, but what practical aspects do I need to consider? Also steel vs. aluminum wheels, which is more practical for trails?

I do not plan on doing any hard rock climbing but would like the ability to drive on moderate trails. if I get bit by the hardcore bug then i would look at upgrading including the suspension.

[BJeepJK]

you'd be cutting it close with them sticking out or not. There stocks are maybe 2" inside the fender and you are getting wheels with 2.25" less back spacing... so they'd stickout just a little.

Thanks atomicmecha, i'm still looking. I want something that looks like the soft 8's but don't want steel, I like the ProComp (Series 8069) or American Racing Mojave with Teflon® (Series 3981). Anybody know of any other black wheels with this look?
I'd better hurry up and make up my mind before there are too many choices, I hate shopping.

[TiredIronGRB]

I can confirm that the Cragar 15X8 4"BS (http://store.summitracing.com/partdetail.asp?part=CRR%2D3425850&view=1&N=700) wheels will fit without modification.

http://www.4x4grace.com/Coppermine/albums/userpics/10001/normal_JK_05.JPG

http://www.4x4grace.com/Coppermine/albums/userpics/10001/normal_JK_06.JPG

http://www.4x4grace.com/Coppermine/albums/userpics/10001/normal_JK_07.JPG

http://www.4x4grace.com/Coppermine/albums/userpics/10001/normal_JK_08.JPG

http://www.4x4grace.com/Coppermine/albums/userpics/10001/normal_JK_09.JPG

http://www.4x4grace.com/Coppermine/albums/userpics/10001/normal_JK_10.JPG

http://www.4x4grace.com/Coppermine/albums/userpics/10001/normal_JK_11.JPG

http://www.4x4grace.com/Coppermine/albums/userpics/10001/normal_JK_12.JPG

http://www.4x4grace.com/Coppermine/albums/userpics/10001/normal_JK_13.JPG

http://www.4x4grace.com/Coppermine/albums/userpics/10001/normal_JK_14.JPG