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DEATH WOBBLE WOES:My experiences
I figured that since there is such a wide spread problem with Death Wobble on Jeeps, and there are so many who don't really know what happened or what to do that I would do a page specific to this topic. There are alot of people who lift thier Jeeps, or have the lift installed for them and really don't know what they are getting involved in, with little or no knowlege of the way the Jeep works. Well. I'll try and explain some of my experiences here. And, as always, if you have a more detailed question, or have had a totally different experience, then shoot me an email email@example.com and we'll discuss it.
Someone asked in the Guestbook... "Can you get DW on a stock Jeep?" The answer is a resounding "YES". DW in a stock Jeep would be an indication of severely worn parts. A friend's '95 ZJ Limited with a 5.2 V-8 began getting DW. On inspection I found that the frame-side joint of the trackbar was worn out. It is an integral part of the trackbar and required repacement. DW was gone afterwards. Hope this helps anyone with this issue.
Death Wobble ("DW" or D/W). It is a hard disease to cure on some Jeeps. It is informally defined by myself as the feeling that the Jeep is going to fly apart. When you have DW, there is no doubt you have it. Imagine a unbalanced tire times 25. Then... you might be at the lower threshold. It is actually a vibration in the front axle that is both vertical and lateral. I have been nuts enough to look out the window at my shakey front end and observe the mele. It isn't pretty, and the truckers that were witness to one incident of DW on the Interstate thought I was about to loose the front end also.
I first experienced DW when I installed a pair of TJ 3" coils on the front of my Grand (ZJ) under a 2" BB. The softer coils netted me about 4" of lift on my Jeep. Every time I would hit a "sharp edge" bump, the DW would set in. I never did get an alignment. At the time, I was running a '94 ZJ front axle, so I still had standard caster adjustment. I adjusted the bolts with the lobes forward... ever so slightly... until the DW subsided. Still, never getting an alignment.
I continued for some time like this until making a swap of my TJ coils for a set of 3.5" coils intended for a ZJ, and a pair of UpCountry front coils that I put out back. I was up to 5.5" now. DW set back in. This time, I had an adjustable track bar and a pair of adjustable Lower Control Arms (LCAs) since the "new" XJ axle did not have provisions for caster adjustment. After the alignment, I still had certain times where DW would re-visit. I adjusted the LCAs a few times and got it sorted out. Well. Right before we took the trip to MOAB, the DW was starting to come back. While at the alignment shop, we did a thorough inspection of the front and found that the trackbar bushing was allowing between 1/4 and 1/2" of play. I had also found during this period that
DO WHAT!?!?!??!! AT WILL?
Well, right before MOAB, it came back. The trackbar bushing was later replaced. BUT. Let me add some more insight. While dealing with the DW, I made more observations. Again the "target speed" was around 56-60mph. But, if I were traveling down the street and hit, say, a pot hole with the RIGHT tire... no effects. If I hit it with the LEFT tire. BOOM!
Here is another key. When accelerating, the ZJ has some torque steer due to the soft coils and the angle of the arms. The ZJ also literally torques under power. ALL of this is actually relieving pressure on the left front tire. Also, when applying pressure either way with the steering wheel, I am actually putting lateral pressure against the trackbar. The angles of the trackbar and the steering linkage don't quite match on mine. So... by "unloading" the left front tire and adding some lateral pressure, I am causing the DW? It would appear so. Further more, I noted that the initial shimmy was more prominent when the transmission was in Overdirve. When the O/D was off, it tended to have less shimmy in it, and I could sneak past the "target speed" without DW. Harmonics, maybe? BUT... Once I got the new bushing in place on the trackbar, the DW was gone. Until the bracket I made for the steering stabilizer broke.
Once again, DW was back. Same old thing. I could induce it at will, or it would set in at the "target speed" or on nome rough surfaces. I hit a set of rail road tracks that were VERY rough at 35 mph and the DW started. (wow!) Once I put the intended stabilizer bracket back on the ZJ, the DW was gone.
Every Jeep is different. Virtually anything that attaches to the front axle can be a contributing source of the DW. Bad unit bearings. Tie rod ends. Track bar. Control arms. Steering stabilizer. The list goes on. If/when you begin experienceing DW, check for any bad components. Get an alignment. And then experiment. The higher the lift (and angle of the control arms), more prone you are to experience this dreaded disease. It is cureable, though your cure may be different than the next guy's.
I later removed the Skyjacker trackbar and installed the steering stabilizer into the OEM stabilizer mount. I installed a Black Diamond trackbar. No DW.>
In an effort to solve some steering problems, I installed the Teraflex D30 High Steering conversion. The deatils are HERE It's relation to this page? In order to install this kit, I had to cut the passenger side sway bar mount. I also need to correct the trackbar angle to closely match the new draglink. I reinstalled the Skyjacker trackbar that mounts into the OEM stabilizer mount. So. No swaybar. No Stabilizer. No Death Wobble. :-)