Yj Wobble (not DW) just wobble

[JeepcrewX5]

I have a 90 yj, 2 1/2" suspension lift, boomerang shackles rear, tow shackles front, quick disconnnect swaybar, no steering mods. I have noticed a side to side wobble upon hitting bumps especially on corners at moderate speeds. I intend to check out the front suspension... but a place to start or things to look for would be nice.. thx for the help.

	Swaybar A sway bar (also stabilizer bar, anti-sway bar, roll bar, or anti-roll bar, ARB) is an automobile suspension device. It connects opposite (left/right) wheels together through short lever arms linked by a torsion spring. A sway bar increases the suspension's roll stiffness—its resistance to roll in turns, independent of its spring rate in the vertical direction.

[currupt4130]

Possibly unit bearings, ball joints, spring bushings, or tie rod ends.

[JeepcrewX5]

Thats along the lines I was thinking, but reassurance is always good, thx.

[Bounty__Hunter]

Is it a wobble, or a jerking of the steering wheel when hitting a bump?

Sounds like bumpsteer, generally caused by the draglink and trackbar not being parallel.

	Track bar A track bar is a component of a car suspension system that provides lateral location of the axle. While the purpose of the rear suspension of an automobile is to allow the wheels to move vertically with respect to the body, it is undesirable to allow them to move forward and backwards, or from side to side. It is this latter movement that the track bar is designed to prevent. It is a simple device, consisting of a rigid bar running sideways in the same plane as the rear axle, connecting one end of the axle to the car body or chassis on the opposite side of the vehicle. The bar is attached on either end with pivots that permit it to swivel upwards and downwards only, so that the axle is, in turn, allowed to move in the vertical plane only.

[JeepcrewX5]

Originally Posted by Bounty__Hunter

Is it a wobble, or a jerking of the steering wheel when hitting a bump?

Sounds like bumpsteer, generally caused by the draglink and trackbar not being parallel.

Its not an up and down wobble like DW, its more like a side to side wiggle that lasts for a very short time, but makes the steering uncontrolable during that short time. Hope thats clear enough.

[JEEPNXJ96]

I Thougth Death Wobble Was Side To Side And Did Cause Uncontrolable Steering? Checkthe Tires For Balance Or Steering Stabilizer

[JeepcrewX5]

From my understanding of DW, limited understanding, a true DW will only stop by slowing to a near stop, this is a very fast wobble that comes and goes upon hitting a bump, and if in a corner, it makes the jeep want to "jump" with the sideways g forces. I just want to narrow this down to the best of my (and fellow readers) abilities. I am looking for all suggestions before I tear into this on Saturday.

[jfrabat]

I agree with bounty; the fact that it happens when you hit a bump leads me to bump steering....

[Bounty__Hunter]

I was simply trying to narrow it down, as DW in YJ's and other leaf sprung vehicles is rare (aren't TJ owners lucky)

A bump can induce DW, but it is more violent than bumpsteer. Bumpsteer is simply the steering wheel turning sideways as the front suspension compresses, then returning to center.

Can you narrow it down from a 'side to side wobble'? If it's violent and requires slowing down to stop the wobble, it's DW. If it is not violent and ends as quick as it starts, it is likely something else.

I would start by going through and tightening all the hardware related to the installation of the lift. Then watch all steering components as somebody cycles the steering wheel from lock to lock, and bounces it back and forth against full lock quickly.

[slo-wrench44]

hmmm, check the unit bearings and also see how much play you have in the rear wheel bearings. mine were going bad and let the rear axle shafts slide in and out about 1/4 an inch caused lots of weird steering issues. like the rear end was slideing when i was comeing out of a turn. the axle shafts are not supposed to move in and out . if so then its time for rear wheel bearings and seals. hope this helps

[cewtwo]

When you said that you haven't modded any steering components does that mean that you have the stock pitman arm? You may want to try a dropped pitman arm. You can get them on eBay for $45 bucks or so. Most rental joints carry pitman arm pullers as do auto parts stores.

That will get your drag link and pitman arm into much better alignment (geometry).

[JeepcrewX5]

After driving freeway speeds again yesterday Im noticing a side to side motion of the steering wheel at high speed, I have some great ideas of where to start due to all of you, Ill let you know what I find come Saturday afternoon.

[jfrabat]

Ahhh... Nothing like a long weekend to spend under the Jeep!

[TwistedCopper]

My money is sitting on it being unbalanced tires, but it could be something else simple like the front end being out of alignment.

I doubt it is related to the trackbar and drag link being misaligned. The trackbar is mounted in a fixed location and not adjustable. This leaves me to believe that it is one of the above mentioned issues.

Did you lose a wheel weight? Are your front tires unevenly worn? Did you whack a curb or rock knocking the front end out of adjustment? All three?

(edit) as for the pitman arm, you should not need one with a 2.5" lift. If those shackles are really tall then maybe, but even then it wont cause the problem you have. I ran my BDS 3.5" kit on a YJ years ago and waited about a month before adding the drop pitman arm. It made no noticeable difference in drive-ability.

	Track bar A track bar is a component of a car suspension system that provides lateral location of the axle. While the purpose of the rear suspension of an automobile is to allow the wheels to move vertically with respect to the body, it is undesirable to allow them to move forward and backwards, or from side to side. It is this latter movement that the track bar is designed to prevent. It is a simple device, consisting of a rigid bar running sideways in the same plane as the rear axle, connecting one end of the axle to the car body or chassis on the opposite side of the vehicle. The bar is attached on either end with pivots that permit it to swivel upwards and downwards only, so that the axle is, in turn, allowed to move in the vertical plane only.

[JeepcrewX5]

Originally Posted by jfrabat

Ahhh... Nothing like a long weekend to spend under the Jeep!

Lmao, too true, but I dont have the back for it anymore, Ive had two back surgeries in the last five years, and I was hoping to do this quick like. Oh well. I do miss turnin wrenches and ending up with xtra supluferous parts . Twisted, i read your above input and I think I will stop at Big O and have them check tires b4 I get too deep in breaking things. Thanks again gang for the input.

[jfrabat]

Originally Posted by TwistedCopper

(edit) as for the pitman arm, you should not need one with a 2.5" lift. If those shackles are really tall then maybe, but even then it wont cause the problem you have. I ran my BDS 3.5" kit on a YJ years ago and waited about a month before adding the drop pitman arm. It made no noticeable difference in drive-ability.

Ditto... I drove my RE 4" without a dropped pitman for a couple of days, and other than the steering wheel not being centered (because I did not realign it), I did not feel any bumpsteer or steering problems (now, the vibrations on the back due to the axle and DS not being alignd and the new CV shaft DID shake the jeep up REAL GOOD at about 30mph, so I may have been paying more attention to that than the steering!)