4x4chick

Since you are the expert, I am sure Jeep is hiring, Go apply for a job and solve all the "it is a Jeep thing" problems for us.

TheDirtman

You are taller too on the new tires by nearly 1" plus the added .39 width is the reason you are rubbing. I assume you are rubbing at ride height, it will be worse when you are flexed out at full lock. Just adding height will not eliminate rubbing. You will also need to run more bump stop to keep the tires from stuffing upwards when you compress the shocks. Now adding lift and bump stops is going to limit travel on you shocks so you will only have around 6"-7" of actually suspension travel making it worse then stock.

You should have a front adjustable track bar and and rear adjustable axle side track car bracket that raises the mount by the sam amount you are lifting.
You should get longer sway bar links or find some used rear links and install them up front. Your rear links should be fine at 1.5" Check for clearance to the track bar bolt on the car tires, It can be an issue with 12.5" wide tires but you are not close to that.

mr72

I presume as an alternative I could either a) don't go off-roading or b) trim the fenders and/or fender liners to avoid rubbing when compressed. Might still wind up running into the sway bars when compressed but if I switch to disconnectable end links (likely) then I'd be able to (likely) tie up the sway bar out of the way when off-roading so potentially mitigate that issue.

Anyway, regarding the lift vs. sway bar rubbing the tire is actually round (duh) and the sway bar is currently 23" off of the ground. If I raise the sway bar (along with the frame) another 1.75" then that puts it 24.75" off of the ground. The chord (I know, geometry) of the tire at 24.75" from the ground is considerably shorter than that at 23", so the tire may actually be less likely to interfere with the sway bar when the Jeep is lifted another 1.75" as long as the sway bar is lifted the same amount. This of course applies only at ride height. When compressed that 1.75" it would still rub the same as it does now and when compressed more it probably would rub a lot, depending of course on how much the axle shifts side to side as only one side compresses. I presume Jeep engineers have sorted that problem out like 75 years ago. Would have to check and see.

That's all a part of the plan. I may washer-up the steering stop for a few weeks until I can get the front adjustable track bar ordered and installed.

Thanks for the advice.

TheDirtman

I understand geometry but I also understand suspension design. Most math guys don't understand the dynamics of suspensions and typically ignore the facts that things move in arcs. Moving one thing in the suspension also affects everything else in the entire suspension and steering. If you don't replace everyone in the suspension and steering with adjustable components and understand how things move and take the time to set up right making a seemingly simple adjustment such as ride height will create issues elsewhere. Things like loss of wheel base, axle shift, shock clearance, coil unloading, sway bar flips, ride quality, cornering stability, roll over risk may all become an issue from adding height.

Adding 2" of lift will also give you more clearance to the sway bar at ride height because your wheel base will be reduced by about 3/8" up front, but as you stuff the tire up the tire will rub unless you add enough bump stop to keep the wheel from stuffing. Up front your track bar will be at a greater angle and create even more axle shift side to side as you stuff the wheels.

When asked about rubbing, most everyone is going to give you a solution for the entire range of articulation not just at ride height. Why spend the time and money on a suspension lift that will likely create more issues when and does not solve the actual problem? Proper wheel backspacing is the fix, either add 1.75" adapters, get new wheels, or put the proper tires on for the wheels.

mr72

Thanks again for all of this input. Like I said I am not going to be changing wheels, just trying to do the minimal light-touch changes to get these tires to not rub during normal driving (on the road).

I drive off road only extremely rarely and then not often rock crawling so not likely to really push the limits of travel, but I fully understand the tradeoffs with respect to potential rubbing and other things. Point is since I drive on the road 99% of the time I will be optimizing for on-road driving conditions.

mr72

FYI for anyone following this thread, I ordered an adjustable front track bar, rear track bar relocation bracket and a pair of Steinjager adjustable front end link disconnects, tripling the cost of my lift project but perhaps doing what's necessary to keep everything working correctly.

I'll report back on if it rubs once it's all installed. Probably a couple of weeks.

spmitchell86

[QUOTE="mr72;4294714"] Just amazing that it can't tolerate tires that are 10mm wider. Go Jeep!

Actually the stock jeep tire is only 225/75 R16... the 255 is the largest they can accept stock (as an option)

Smudgeontheglass

It is interesting the argument going on the backspacing issue. That is what this whole argument is, everyone saying there isn't enough backspacing for the taller and wider tire and the OP not agreeing with that fact.

The easiest and least expensive fix would be a 1.5" wheel spacer. This would change the stock 6.25" down to a more acceptable 4.75". This is just enough to get to a 35" tire and have the minor rub you are seeing with your 33s. They push the stock wheels out to just the bare edge of the wheel well with no poking out. Under full fender stuff you can still fit the stock tires with no rubbing. If you ran the mopar mud flaps the tires would still have full coverage. 1.5" spacers are wide enough to cover the wheel stud as well so no worries about them fitting poorly.

The only downside with spacers is that you have to treat them as another set of wheels and torque, then re-torque them separately. Loctite and a torque wrench are your friends.

mr72

Except for the fact that this tire is not appreciably taller or wider than the stock size tire. It's maybe 3/4" taller and less than 1/2" wider total. It is literally the very next size tire you can by.

I'm not disagreeing with the fact that Jeep failed to design in sufficient tire clearance to accommodate the expected range of reasonable replacement tires on stock wheels.

I disagree that changing a fundamental design element of the suspension like the wheel offset (or backspacing) is an acceptable solution. Whether or not you agree or understand, it's not acceptable to me, so I'll seek another solution. I understand most of the readers of this forum are not interested in helping me find an alternate solution, so I'm on my own.

Smudgeontheglass

Just as a question, is the front air dam still in place? You would rub on that first well before the sway bar. People have rubbed on that with sway bars disconnected on the stock tires at full turn/stuff.

Different tire manufacturers end up having different tire measurements as well. I would not be surprised if the 255/70/18 Goodyears were noticeably smaller than the 265/70/18 of your Coopers. The Coopers may also have a more squared off tread pattern meaning they sit wider as well.

And as far as solutions go, Thedirtman is one of the most knowledgeable individuals on this forum, try to understand his response first before anyone else.