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Unread 01-05-2012, 02:14 PM   #1
Mol
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DEFINITIVE WHAT SIZE TIRE/Wheel/SPACER/BACKSPACE THREAD

I have noticed an influx of what size tires, or will this fit, or will this look funny threads in the past few days. I believe there is something around 7 just on the first page.

So....

I took it upon myself to finger back through the pages, as far as page 9 (12/16/2011) and found the following. This was not even utilizing the search function - imagine what I could have found, then.

ALSO - I have quoted the "WILL IT FIT" thread, by NeaKid, and added a few more applications, in red:

__________________________________________

The JK with stock wheels, no spacer, no lift

32" tires: no rubbing
33" tires: some rubbing can be cured with minor trimming of the stock airdam (applies to 12.5" wide tire)
35" tires: don't try (12.50" wide tire will rub without aftermarket wheels or wheel spacer)


The JK with stock wheels, 1 1/2" wheel spacer, no lift, Bushwacker flat-top flares

32" tires: no rubbing
33" tires: no rubbing
35" tires: rubbing that can be cured with trimming pinch-seam, possibly no trimming if you're sticking to the street only...watch those speed bumps
37" tires: don't try

The JK with stock wheels, 1 1/2" wheel spacer, 2" lift

33" tires: no rubbing
35" tires: some rubbing that can be cured with minor trimming of stock airdam, and fender flares/liners. Pinch seam trim recommended.
37" tires: don't try

The JK with stock wheels, 1 1/2" wheel spacer, 3" lift

33" tires - no rubbing, looks silly (lots of space between fenders and tires)
35" tires - no rubbing, trimming of pinch seam recommended
37" tires - minor rubbing with stock flares. No rubbing with flat flares. Proper bumpstop length and pinch seam trim necessary.

The JK with stock wheels, 1 1/2" wheel spacer, 4" lift

33" tires: no rubbing - entirely too much lift for the tire size
35" tires: no rubbing
37" tires: some rubbing (minor), none with flat flares - proper bumpstop length and pinch seam trim neccessary
38" tires: be careful - flat flares necessary, trimming necessary
39" tires: don't try without 1" body lift, trimming, and flat flares

The 1.5" wheel spacer will work as an alternative to new wheels, but many will recommend the replacement of your stock wheel as a safer alternative. This is an ongoing debate; regardless of your opinion on the matter, when buying a NEW AFTERMARKET WHEEL for a 12.5" wide tire, 4.7" backspacing is the MAXIMUM acceptable amount of backspacing to avoid using wheel spacers. 4.5" is recommended, and 3.75-4" is necessary for 14.5" wide tires.

MORE ON WHEELS - ADDED FROM DELETED POST BELOW

A Wider rim width will not effect the proximity of the tire to the steering components, sway bar end links, or fender flares/liners/wind dam - only a change in tire width will do this. A wider narrower rim will produce a ballooning effect on a wider tire, while the wider 8-10" rims will produce a flatter sidewall on the wider tires. The stock 7.5" wide rim is sufficient for a 12.5" wide tire, but as you mentioned, the 6" backspacing will cause rubbing in the rear on the swaybar end link, and rubbing on the front at full lock.

This is where the 1.5" wheel spacer comes into play, again as you already have mentioned. It effectively creates a total backspacing of 4.5". For that matter, a 1.25" wheel spacer will work as well, but it pushes the max limit for backspacing out of many peoples' comfort zones at 4.75".

The wheel spacer is argued as an inexpensive bandaid fix to make tires work - in all reality, it is not inexpensive. A hub centric wheel specer set of TWO will run about $100, or $200 for a full set of four. You're well on your way to an inexpensive set of steel rims at this cost, and you haven't yet factored in the cost of the stock tire holder extension bracket for your larger spare tire, or the extended bumpstops for the tailgate, or the tailgate reinforcement kit. The proponents of wheel spacers will argue that for years and mile upon mile, they have run spacers with no issues, and many have. But trust the first time you see a wheel spacer sheer off of the hub on the trail, you will second guess the setup

When looking towards aftermarket wheels, you have 3 things to consider:
  1. Are the hub or lug centric? Hub centric is ideal, knowing that your wheel perfectly centers itself around the hubs center without force from the lugs to properly allign.
  2. What is the backspacing? I consider 4.7" the max allowable, but would suggest looking for wheels with 4-4.5" if you ever will consider going wider than a 12.5" tire.
  3. What is the rim width? Again, the stock wheel at 7.5" wide is sufficient for a 12.5" wide tire, but if you're going aftermarket, look at 8-10". The 8" width will be great for 10.5-13.5" wide tires. 14.5-15.5" tires should probably be mounted to 10" wide rims. Above and beyond the aforementioned "ballooning" effects, or lack thereof, a wider tire on too narrow a rim will be more prone to breaking from the bead at lower pressures.
Obviously - we also have wheel and tire weight to consider. Steel rims are heavier than alloys, D and E rated tires are heavier and stiffer than C rated tires. Take all of this into consideration. Many of the tires for our 17" wheels are D rated and D rated only. Good for the heaviest Wranglers to date, but not as plyable of a sidewall (doesn't bend and conform to the trail as well at lower PSI as the C rated tires we ran on our CJs, YJs, TJs). Avoid E rated tires if possible - you're not pulling a 10K pound trailer with your JK, and if you are - hook your GoPro up to the JK so I can witness the catastrophe

FITMENT OF LARGER TIRE ON THE STOCK CARRIER

It is tough to determine whether a larger tire will fit on the stock carrier without adjustments being made, because of the various different sizes of tires available, and the descrepencies between the actual inflated size and the advertised size of a given tire. Both diameter and width effect the fitment of a larger tire to the stock carrier. A wider tire will make contact with the tailgate/carrier before the stock carriers lugs have come through the STOCK WHEEL. A larger DIAMETER can make contact with the stock rear bumper.

These Guidelines are generally speaking, and not set in stone, and each assume a tire width of 12.5":

33" tire on stock wheel - will not make contact with the stock bumper, will make contact with tailgate/stock carrier. Requires a stock tire carrier extension bracket
35" tire on stock wheel - same issue as the 33, but now with the possibility of contact with the stock rear bumper as well, depending upon actual inflated size
37"+ tire - DO NOT TRY


Your solutions are one of three:
  1. An aftermarket wheel with the backspacing previously suggested will clear width issues on the stock carrier, but you still have the possibility of rubbing the stock rear bumper. Minor trimming can alleviate this.
  2. Buy the tire carrier relocation bracket, located here,
  3. Buy an aftermarket rear bumper with swingaway tire carrier, or a body mounted swingaway tire carrier, or a combination of both. Whatever suits your style/function/budget.
Solution numbers one and two will most likely require you to buy extended tailgate bumpstops. Daystar makes these - inexpensive, and necessary to ensure that your tire is well snubbed, and not rattling your tailgate skin to pieces. They can be found here. Most aftermarket tire carriers will come equipped with the equipment necessary to properly secure your tire...unless you buy from the Chinese. Just sayin'

Many of our fellow forum members have found security in buying a tailgate reinforcement kit, when running a heavier tire or tire/wheel combo on the stock carrier. Believe it or not, the hinges are not the weak point on the tailgate, they're plenty strong. It is the spot welds on the tailgate skin that can separate from undue stress. This should not pose an issue if your tire is properly snubbed, BUT, for only $30, you can play the better safe than sorry game. Here is the reinforcement kit.
___________________________________________
Update - here is a helpful link that I believe is relevant to the subject
15" WHEELS THAT WILL FIT WITHOUT RUBBING
___________________________________________


FIRST -

here is the FAQ -

you will notice it is conveniently located in the stickies at the top of the first index (the page you are always on). I understand that it does not answer every scenario, which is why I have provided the following below (the search function will net you even greater results)...

Deciding between 33s and 35s on a 4-door

Will my tires look too small

Would 35" tires and bushwacker flat flares rub w/o a lift?

305 70R17's anyone?

Need pics of 2door deep water blue on 33s

Can a stock rubi drivetrain hold up to 37s?

Tires.....Sorry

Tires. I think I have settled on 285/75R17. Now I need suggestions

Going to 37s from 35s

Seeking wheel advice!!!!

Tire/spacer question

Good Wheels For Rubi

Wheel Size on 2012 Rubi Unl

Rew Rims, New TPMS sensors?

Stock Height on aftermarket rims and tires?

Verifying new tires on stock wheels

About to buy some wheels - will these fit?

Tire Size

Wheel Space explain and tire size help

What tires to buy?

Pics with a lift and stock 32s

Will they fit?

Falken Tires

Poll: Wheel Locks

Cheapest 35" tires

35 without regearing?

Who has 5.13 gears with 35s and 6 speed?

Clearing 33s on Jeep

Poll: AEV Pintler vs. AEV Savegre Wheel

New Trail Grappler Sizes

Comments on these wheels

Tire Size Recommendations

Tire Size - Help a new jeeper out

Need some advice

10 jk islander - stock/largest tires that fit

Please help....2door 2.5 lift with stock tires

Steel or aluminum rims?

Painting stock wheels

Cons to running 16 inch wheels

Need advice on backspace for my tire/wheel pkg

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Unread 01-05-2012, 02:21 PM   #2
jwmbishop
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So will my 35x12.5r17s mounted on 17x10x3.5bs beadlocks on a 2.75 lift rub on an orange JK?
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Unread 01-05-2012, 02:25 PM   #3
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Quote:
Originally Posted by jwmbishop View Post
So will my 35x12.5r17s mounted on 17x10x3.5bs beadlocks on a 2.75 lift rub on an orange JK?
I'm ignoring your sarcasm and answering anyway

No - but your tires will protrude from your fender flares big time! I'd recommend a wider tire for those wheels, or vice versa
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Unread 01-05-2012, 02:41 PM   #4
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lol

You know me too well already! Of course on a blue JK it WILL rub...

Actually according to my guru - the 12.5 on a 10 inch wheel makes the sidewalls nice and straight at street pressure - when aired down to 8 all the bulge makes em act like tractor treads on the rocks. Haven't ordered wheels or tires yet as I too am hesitant - the bs and protrusion has me concerned, and I am considering a 16x9 with 35s and that WILL rub a bit until I work the inner liners (or will probably have to use 1/2 spacers and cut or remove the stock fenders). I could go 33 - but we're having a hard time matching 17 stock rim/tires to the 16 off road rim/tires for easy swapping without having to change the computer!
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Unread 01-05-2012, 02:47 PM   #5
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IMO, that "will it rub" FAQ is missing something critical...AFTERMARKET WHEELS.
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Unread 01-05-2012, 02:49 PM   #6
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Quote:
Originally Posted by goldenglory18 View Post
IMO, that "will it rub" FAQ is missing something critical...AFTERMARKET WHEELS.
Jog back up there and take a second look...towards the bottom. If it isn't enough, I'd be happy to elaborate further.
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Unread 01-05-2012, 02:53 PM   #7
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Quote:
Originally Posted by jwmbishop View Post
lol

You know me too well already! Of course on a blue JK it WILL rub...

Actually according to my guru - the 12.5 on a 10 inch wheel makes the sidewalls nice and straight at street pressure - when aired down to 8 all the bulge makes em act like tractor treads on the rocks. Haven't ordered wheels or tires yet as I too am hesitant - the bs and protrusion has me concerned, and I am considering a 16x9 with 35s and that WILL rub a bit until I work the inner liners (or will probably have to use 1/2 spacers and cut or remove the stock fenders). I could go 33 - but we're having a hard time matching 17 stock rim/tires to the 16 off road rim/tires for easy swapping without having to change the computer!
Walker Evans makes their wheels from 3 3/4" to 5" backspacing at 1/4" increments in a 17" wheel, if you're not set on 16s
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Unread 01-05-2012, 03:52 PM   #8
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I was considering 16 for the extra sidewall "squish" - but walkers are my first choice for wheel. My buddy has em on his TJ and we never get tired of the complements for looks! The 35s on 15s really form to the rocks....
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Unread 01-05-2012, 04:05 PM   #9
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Quote:
Originally Posted by molshove View Post
Jog back up there and take a second look...towards the bottom. If it isn't enough, I'd be happy to elaborate further.
Thanks Molshove,

Just to clarify, and I think I understand this, but want to make sure for me and anyone else. The backspacing of the Stock Jeep rim is 6" right? So a 1.5" wheel spacer would equal the same as an aftermarket wheel with 4.5" of backspace, correct?

To go further, if the above is true, does that only apply when the rim is 8" wide? Would that 4.5" of backspace change if you go to a 9" or 10" wheel?

I agree, there's a lot of the same questions on this asked over and over, but there are many variables that go into it like the backspacing of aftermarket rims, as well as the application (e.g. how much flex you care about).

Last, maybe a good tire conversion chart or formula link would be helpful. I use this one, but maybe you know another? http://www.redrock4x4.com/tireconversioncalculator.html
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Unread 01-05-2012, 04:07 PM   #10
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Quote:
Originally Posted by jwmbishop
I was considering 16 for the extra sidewall "squish" - but walkers are my first choice for wheel. My buddy has em on his TJ and we never get tired of the complements for looks! The 35s on 15s really form to the rocks....
Only problem with 15s and 16s, but especially 15s, is today's tire manufacturers are producing fewer size selections with those size holes. As time passes, your selection will diminish further still
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Unread 01-05-2012, 08:03 PM   #11
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Great Googly Moogly....

Molshove! Thanks for all of the great information but, for all of the jeep newbie boneheads like myself that are overwhelmed with the plethora of info can you help me out? Confoosion has set in!

Im not sure I made the right decision......

I bought a 2011 JKUR, put on a 3.5 inch lift AND...... just last night (after I thought I had this all figured out) I ordered my wheels and tires. Right now I am one of the funny lookin roller skate looking jeeps with the factory wheels/tires. I bought 17X9 in wheels with 4.5 backspacing and 35X12.5X17 BFG KM2's.

Im hoping I did the right thing cause I wasnt expecting to have to get flat flares, trim pinch seams, etc etc. I realize now after reading your posts I will need to atleast buy the beefed up spare tire carrier???

Arghhhhh!

Brian
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Unread 01-05-2012, 09:57 PM   #12
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Quote:
Originally Posted by RubiHD View Post
Molshove! Thanks for all of the great information but, for all of the jeep newbie boneheads like myself that are overwhelmed with the plethora of info can you help me out? Confoosion has set in!

Im not sure I made the right decision......

I bought a 2011 JKUR, put on a 3.5 inch lift AND...... just last night (after I thought I had this all figured out) I ordered my wheels and tires. Right now I am one of the funny lookin roller skate looking jeeps with the factory wheels/tires. I bought 17X9 in wheels with 4.5 backspacing and 35X12.5X17 BFG KM2's.

Im hoping I did the right thing cause I wasnt expecting to have to get flat flares, trim pinch seams, etc etc. I realize now after reading your posts I will need to atleast buy the beefed up spare tire carrier???

Arghhhhh!

Brian
Ahhhh, this thread has already paid for itself...if all "will it fit" questions stay in one thread, I will be a happy camper

You're perfectly fine on lift, and perfectly fine on wheels

The most typical problem with spare tire on stock carrier fitment is when the larger tire is mounted to the stock wheel. Your odds of fitting with the aftermarket wheel are much greater. With a stock wheel, you would need the tire carrier extension bracket, but this won't apply to you. Depending upon actual inflated size, you might need to trim the stock bumper, but hopefully not. If you fit fine (clear the bumper at the bottom of the tire), and the backside of the tire keeps off of the tailgate, you will want to make sure that the stock tire snubs (two rubber black things mounted to the tailgate skin) make solid contact with the back of the tire after the tire is bolted on. If not, you can spend $15 and buy longer ones made by daystar. These will ensure that the tire does not flop around over bumps and such, separating the tailgate skins. Your hinges are plenty strong enough to support the extra weight.
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Unread 01-05-2012, 11:25 PM   #13
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so you are saying that when i put my 28" spinners on i will need to make sure that i get proper BS .



good thread. helps me. even though my broke butt can't get tires for now.
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Unread 01-05-2012, 11:51 PM   #14
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Originally Posted by JJAMISON_
so you are saying that when i put my 28" spinners on i will need to make sure that i get proper BS .

good thread. helps me. even though my broke butt can't get tires for now.


Your broke butt is gettin broker, you just wait
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Unread 01-06-2012, 12:15 PM   #15
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So you're saying I can't fit 35s on a stock JK?




Just kidding.
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