Death Wobble (I've searched and read)

[asatxj]

91 limited 4x4
I have REALLY bad DW and I've read lots and and spent lots. tires balanced, new track bar, newer stock lca's ALL new brake parts (rotors calipers etc) all suspension bolts tightened. When I put the new TRE at the pitman arm on yesterday IT GOT EVEN WORSE. Now I won't drive it. I'm down to one vehicle for the next two weeks till I have more $$ for parts- Wife is unhappy-----. Someone want to point me in a direction?

 

[Matthew Currie]

Checked the ball joints? Steering damper? Binding axle universal joints shouldn't create DW by themselves, but might set it off it if there are other problems.

You mention a new tie rod end, but you didn't say whether you had it realigned. If not, that's a priority.

 

[asatxj]

I put the TRE at the Pitman arm on so realigning wasn't an issue. Damper is new. Lt side ball joints are new, right side is tight, Hubs are both new. Didn't see any issues with ujoints binding. Keep the ideas going, I don't want to throw random $$$ at it so any intel will help.
Thanks!
ASAT

 

[jcnoble]

At what point did the Death Wobble start? Lift kit or something else?

 

[asatxj]

About a month after I got new (used) wheels and tires. Since they've been balanced and rotated, a new brake rotor added. I noticed today that there seems to be a little play in the steering box. I can grab a wheel and move it and the pittman arm moves a small amount. Is there an adjustment to tighten up free play there or should I just put my spare box in? I did look out the window the other day when it was doing DW and the wheel is going in and out-like turning- not up and down.

 

[Nick]

Eagle has brought up that in the past he has experienced DW in a a ZJ w/ warped rotors. You mentioned new brake rotor, did this make it worse?

 

[asatxj]

It made no difference. But the problem has been getting steadily worse. The only improvement was the new track bar but after a day or so it was DW again.

 

[jdougn]

This checklist is something I printed from XJNation but I couldn't find his original post. Some things have been added from other sources.)

FRONT END CHECK LIST:
(Check your Haynes or Chiltons manual to id part locations. "*" means do with jeep on jack stands.)

1. Tire Balance
(Watch them do it if you can. A lot of shops don't do it right.) Clean your tires & rims before taking the Jeep in to get the tires balanced. Most shops use a high speed rotating balancer with digital scales but make check. Occasionally a shop will just use a bubble balance on larger tires and they don't do well. Make sure the mechanic removes the old weights before balancing. If at all possible use rim mounted weights. A good balance will read zeros on both digital scales.

2. Lug Nuts
Double check all lugs nut for tightness, especially after having it in the shop.

*3. Loose suspension or steering parts
Put jackstands under the front axle and check all suspension & steering for loose parts. Banging around with a rubber mallet might help. (Everything feels good with weight on it.)

* 4. Ball Joints
Check ball joints for play. While the vehicle is on jack stands, put a long pry bar under the tire and try to make it move up & down. Watch the ball joints and if any movement at the joint they should be replaced.

5. Trackbar
Remove frame end of trackbar and check joints.
(If it's a stock trackbar and you can move it left-right by hand the bushings are bad. Or, if you can move the bushing with your fingers they're bad.)

6. Alignment
With bigger tires, toe in should be set close to 0".
Do this with jeep on the ground and wheels straight ahead. (I like straping a straight edge horizontally at the centerline of each front tire so there is something easy to measure to. Or just make sure your measuring to the same location on each tire.) The measurement should be a max 1/8" less in the front than in the back. You can adjust this yourself on the tie rod.

7. Shocks
- The pin on the top of the shock can become loose. With hard off road use the rubber bushings can fail. With weight off the front tires, if can twist the shock side to side very much, or if there is a clicking noise, the bushings need replaced.
- If there is oil running down the side of the shock it needs replaced
- With the jeep in normal position jump up & down on the bumper. The jeep should stop bouncing much with 1-2 bounces.

* 8. Steering Joints
Check all steering joints without weight on the front. with the jeep turned off, reach up from below and grab the steering column just before the gear box. Rotate the column by hand as you watch each joint from the pitman arm on down to the tires. Watch for play at each joint.

* 9. Hub bearings
With the front on jack stands, grab the top & bottom of the tire and try to wiggle the tire in & out. If there is play, the hub bearing is bad or wheel nut is loose.

10. Steering box
Rock the steering wheel side to side and make sure you see a coresponding movement at the pitman arm. Five degrees or more of steering movement without moving the pitman arm is probably too much.

Let me add a couple more:
* 11. Control Arms
This may be a problem in jeeps that have off roaded. Bang on both ends of the upper & lower control arms. If there is the sound of metal on metal the c.a. bushings need replaced. If questionable, but jack stands under the frame and remove the control arms to visually inspect the bushings. The rubber part should not have significant cracks or tears.

12. Badly worn or damaged tires could cause "wobble" also. No easy way to check without just replacing the tires.

Again, hope this helps.
Doug

 

[asatxj]

Thanks Doug, I think all of the mentioned are ok but I'm going to get some new shocks and perhaps swap out the steering box as it has some play. Can anyone give me the adjustment procedure for it before I yank it?

 

[hackedxj]

I'd really look at the tires since you bought them used. I've saw a lot of DW problems caused by unevenly worn tires. Balancing unevenly worn tires will not help.

 

[92xj242]

Another thing you should try that can be overlooked. I actually broke one of the supports on the top trackbar bracket. It is a big metal braket that bolts to the frame and it has a support in it that broke after a wheelin trip and i could not figure out the problem for a long time But I toook that braket off and I saw the crack. Also the steering box may play a factor in it. Mine wore out and the steering was real loose but i never got death wobble from it.

 

[asatxj]

Track bar brkts are TIGHT as there is no bracket (nutstrip) they use individual nuts for each bolt. and I cranked them down really well.
News flash I did notice one of my Doetsch shocks (RE kit) had a problem with the lower bushing. I think I'll get a couple of new cheapies and see if that helps. BTW how much in inches would you estimate 5* of play in the steering box amounts to?
It seems that we are narrowing this deal down to
1 steering box
2 shocks
3 a TRE that I haven't replaced yet
BTW tires are 31" bfg at's 50% tread worn very smooth no road vibes from them.

 

[carnuck]

I just fixed this in mine. Some excess slack is hiding somewhere (or a bad tire that doesn't show till at speed) so toe-in your tires a little extra. Made mine disappear!

 

[Atl-Atl]

I had all the same problems as you, and did all the same things to fix them. But none of it worked. I too got a set of used BFG all terrains with about 50% tread on them, 31x10.50s. I had them balanced I rotated every tire combo possible and nothing helped, until I got new wheels and tires. Even with tires that appeared to balance on a machine, and picking the two best of the four to go on front, it would still DW REALLY bad. I came to the conclusion that I just need new wheels and tires. So I got some cheap steelies new and some retreads and they are great. It doesnt wobble at all even at 75 on the highway. Id stop wasting time and money on the other parts and just get some new wheels AND tires.

 

[johnnyc]

The two mods that have made the biggest difference for me have been -

1) RE LCAs and UCAs. Take a look at the stock control arms. They're formed steel (is that right?), which are pretty flimsy.

2) Big Daddy tie rod to replace the stock unit, which is also on the flimsy side.

My problem was mostly a bad shimmy, but I did experience the DW a couple of times. But I haven't had a problem in quite a while (knock on wood).

 

[cwlongshot]

Personally,
I would look VERY HARD at those tires. I LOVE BFG's I am not bashing them. I am saying used tires can and do do it VERY OFTEN!!! Direction a tire is run is not supposed to matter any more......I am old school and have seen far to many times a good tire go bad from being run in a different direction.

Barrow a set of tars from a buddie that are known to be good and go for a ride. I'll bet you a beer it will solve your problem.
I have had DW more than once, the first time was about a month after installing a set of used, unmarked BFG AT's. These where NOT marked for direction either. Must have broken a belt or something and DW started!!

Good luck!!

CW

 

[yardape]

Another long shot,... I had death wobble on a ZJ I recently bought. Found out the tires were inflated to over 40 lbs. After taking them down to about 35 the world was good again.

 

[asatxj]

Wheels are Grizzlies all straight. I'll put my old ones back on shortly and see if that helps. I'm putting shocks on today cuz I know one of them is bad. Report after that's done this afternoon.