Fitting 31's w/ 2" BB

I know everyone says that technically you need 3" + to clear 31's without rubbing, but I'm wondering what alternatives I have.

Would it be possible to simply adjust the bumpstops and steering stops without losing too much articulation or turning radius? It looks like there is close to enough room in the wheel wells for 31's (I currently have 30's). I don't do any hardcore wheeling, so I don't need that much articulation anyway. BTW, it's a 2000, so I'm sure that makes it less likely to fit, but I figured I'd see if anyone has done this.

Thanks!!!

treadLightly said:

I know everyone says that technically you need 3" + to clear 31's without rubbing, but I'm wondering what alternatives I have.

Would it be possible to simply adjust the bumpstops and steering stops without losing too much articulation or turning radius? It looks like there is close to enough room in the wheel wells for 31's (I currently have 30's). I don't do any hardcore wheeling, so I don't need that much articulation anyway. BTW, it's a 2000, so I'm sure that makes it less likely to fit, but I figured I'd see if anyone has done this.

Thanks!!!

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My wife's Xj has 31's with a BB, it is only used on-road. With OEM rims you'll rub on the LCA's, like if you didn't already know with the 30's. My wife's has wheels with 3.75" BS, it rubs on the fender flares when going in reverse, like pulling out of the driveway. HTH

Ok, we lift to maintain or improve axle articulation and fit larger tires....You want to limit articulation and turning raduius in order to fit the larger tires.

Just ask yourself if it's worth the trade off. For some, it is, for some, no.

TOZOVR said:

Ok, we lift to maintain or improve axle articulation and fit larger tires....You want to limit articulation and turning raduius in order to fit the larger tires.

Just ask yourself if it's worth the trade off. For some, it is, for some, no.

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Not so fast, Mate.

We lift to improve ground clearance. We also run larger tires to improve ground clearance. "Articulation" is a word that gets thrown around a lot recently, but I'm not certain how many people know what it means, or how it applies.

Let's start with answering the question: According to Ed Stevens' extensive research, you can run 31" tires on stock rims with ZERO lift. Yes, they will rub the lower control arms at full steering lock -- and they will do the same thing even with 4" or 6" of lift.

Secondly, the combined experience of many XJ owners has shown that without cutting sheet metal and flares and removing the inner fender liner, the largest tire you can run without hitting the inner liner at full suspension compression is a 235/75R15 (or equivalent). Doesn't matter how much lift you have, unless you extend the bump stops and/or start trimming, any tire larger than a 235 will rub. So the limitation on the compression side of "articulation" is the bodywork, not the lift. Of course, if you lift enough to run longer shocks, the shocks may stop compression travel before the tires hit the body -- but since shocks aren't designed to act as bump stops, that won't last very long.

I run 30s on a stock XJ off-road, and I've seen a stock XJ on 31s at my local Auto Zone (although I don't think that guy takes his off-road). You can run 31s with a budget boost. Whether or not that's anything close to an optimum setup depends on how you plan to use the vehicle. Personally, I think a budget boost and 30" tires is a well-balanced combination, and 31s with a 3" lift is a well-balanced combination.

BTW --

Ed's research was done on an early XJ. On the '97 and newer, the rear wheel arches/flares are different or the axle was moved slightly farther back in the opening, and 31s may hit the rear bottom corner of the flares. Running the tallest of the 4 available factory bump stops in the rear might be sufficient to alleviate this.

heheh I was waiting for you Harwood. :wave:

I said articulation AND larger tire (nee More Ground clearance)

Unless you Lift AND fit larger tires one thing will suffer.
Keeping the tires on the ground in a cross axling situation will suffer though you will gain clearance at the pumpkins...


Basically it comes down to what you are willing to sacrifice to gain clearance at the diffs....turning radius and forward drive in a crossaxle situation? Than adjust the stops and go nuts!

Not saying one way is correct and one is wrong.

I think the biggest factor in wether or not they will fit is how big the 31 actually is. The smaller 31's could fit with no lift but my 31(measured a hair over 31") did not fit with no lift. They fit with the 2" BB and fencer trimming but I could not unhook the sway bar or it would eat the fenders.

Weasel said:

I think the biggest factor in wether or not they will fit is how big the 31 actually is. The smaller 31's could fit with no lift but my 31(measured a hair over 31") did not fit with no lift. They fit with the 2" BB and fencer trimming but I could not unhook the sway bar or it would eat the fenders.

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Right -- I'm guessing you did not extend the bump stops, which (beneath our apparent disagreement) is what both TOZOVR and I said needs to be done... with or without a lift.

bumpstops.....when io put my lift on no one mentioned anything about bump stops. I think i just barely figured out what the heck they are. is it a good idea or with a smaller lift. I havent had any rubbing what so hell on trails, articulating, or anyting. All i know is i cant disconnect sway bars or my stock brake lines are gonna say bye. haha

You can run stock brake lines on about 4" of lift a long as you unbolt them from the "frame" mount....

I have a 2" RRO BB and run 31 x 10.50 TSLs. They rub the fender in the rear and the fender liner in the front, but not enough to be much trouble. I agree that it would be better with more lift, but it works pretty good as it is.

Before swaybor discos


After discos

96country said:

I have a 2" RRO BB and run 31 x 10.50 TSLs. They rub the fender in the rear and the fender liner in the front, but not enough to be much trouble. I agree that it would be better with more lift, but it works pretty good as it is.

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They would do the same thing even with twice as much lift if you didn't extend the bumpstops.

Eagle said:

They would do the same thing even with twice as much lift if you didn't extend the bumpstops.

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I just meant that they work, not that they wouldn't rub even with more lift. The rubbing is not bad, and hasn't done damage to either the tires or the fenders. I know I need extended bump stops, but I am going to do that when I put on my lift.

I have the 2" BB and 31s Re-Treads on stock wheels. Works out good. Rub at full turn, but they stuff pretty well. Have done a good amount of trimming also.

GREAT INFO!! I JUST JOINED AND I LOVE IT!