1998 ZJ Death Wobble:

twistedjeepster

twistedjeepster

Just another American with a gun!
Joined
May 25, 2009
Location
Kannapolis,NC
I have a 98 ZJ that has a horrible death wobble and has had it for some time. The jeep belongs to my wife and her ex put a shade tree lift on it which started the problem. I had a 4.5" rough country lift on it with a 5" drop pitman arm thinking that would help the problem (she wanted it lifted anyway) but it did not help at all. I know it needs a new steering box because it has a lot of play before the tires will actually turn. I am just wondering what else should have checked/replaced just to cover all the bases. I did do a search on here and did not find a thread on the subject which is why I started a new one. Any info would be greatly appreciated.
 
What are the current alignment specs? (especially caster)

The 5" DPA is unnecessary. Did you also install a track bar drop bracket? If not, that could be a potential problem. The drag-link and track bar should be parallel to each other. Using a DPA without a TB drop bracket moves the DL/TB relationship out of parallel causing bumpsteer and poor overall handling. IMO, a much better setup would be using the stock pitman arm and an aftermarket adjustable track bar.

If you've had DW for any length of time, its also possible that a lot of bushings in the front end are shot. Check them all for play (TB, TRE's, LCA's, UCA's, steering stabalizer). Any loose component or free play allows DW to start.
Here's a thread from JF with some info about DW. http://www.jeepforum.com/forum/showthread.php?t=124861
 
What kind of track bar do you have on it? If it is adjustable make sure the lock nut is tight.
 
It does have an adjustable and the nut is tight on it I made sure of that. All the bolts on the front end are tight and secure. Should I just replace all of the bushings, ball joints, along with the steering box.
 
have you had it aligned by a good shop recently? the play in the steering could just be your alignment being off. before you just go replacing bushings you should check them out. have somebody turn the wheel back and forth while you look at the trackbar bushings. if there is any sort of play thats your problem.
 
Get the DPA arm off the jeep. Like stated above it is totally unnecessary unless you are running a bracket to drop your track bar as well. If it is still giving you DW after that, and all the bolts are tight, then adjust the tow. The jeep should be towed in 1/16 to 1/8 of an inch. If it is still giving you DW check all your end links.

a good thing to do as well is have someone turn your wheel full lock to full lock and then shimmy it while you watch the front end... I had terrible DW and once i did that i found my front track bar bolt was loose.
 
Have the alignment checked especially caster, also make sure the steering damper is good. As stated previously make sure all the bushing are good.

At 4.5" of lift the control arm angles are getting questionable and I have seen a DW problem fixed on a XJ after installing control arm drop brackets, unfortunately there are none available for a ZJ that I know of, so you would be looking at a long arm conversion. Before I went to that extreme I would make sure everything in the front end was good and tight, hub bearings included.
 
Track bar, caster adjustment, the loose steering box, and the drop pitman arm are the likely culprits. Throw the dpa out and put the stocker back on, check every joint and bushing in the front end (particularly the frame end of the track bar where it bolts on) and get the alignment checked.
 
Thanks for the advice guys I am going to have to get under there some time and look at all those options. We are not driving it at the moment because of the loose steering and DW so I have plenty of time to tinker with it and find everything that is wrong with it.
 
Back
Top