Questionhi! I have a 98 coil spring wrangler 4.0, with about 90k miles on it. The 31
inch, 10.5x15 tires are overdue for replacement.(unfortunately i haven't
raised the money for new tires and alignment yet). i bought the jeep used, so
i am not sure if there is a very moderate lift kit on it or not, but it always
handled exceptionally well. a few months ago a front end wobble or death
shake (side to side) started to develop, which happens over 40 mph,
whenever I hit a bump in the road, so it could be resonance, as in bikes. it
stops when i hit brakes. i haven't dared speeding up. a few weeks ago it got
so bad it ripped the mirror out of my glass. i used to be a jeep tour guide in
Sedona, AZ, (very rough terrain) and I have seen this problem on several of
our tour jeeps, but they all had 4-6 inch lift kits. my colleagues used to call it
"death rattle"... our mechanics seemes unable to fix this problem...
the car seems stable otherwise. neither tires nor rims seem damaged. is this
alignment, shocks, steering components, swaybar, ball joints, or a
combination? what else could it be?
help!!!
thanks a lot, regards, Roland
AnswerHi Roland,
Yes, this is definitely an issue with Jeeps -- more so on lifted ones, of course. However, even factory ones have seen issues. The common first component is the Steering Damper (part#52088959AB), which has been a problem for a long time. I've seen aftermarket ones that seem more stout, but this *is* a revised unit. There is a TSB that references this concern, #19-003-06.
Aside from that, there have also been problems with the ball joints and control arms in these things. I've even seen tires filled halfway with water (popular in 4x4's), or even fix-a-flat that's broken loose, exhibit something like this as well. The TJ has some long steering components, and that lends itself to vibration anomalies. Take a good look at all of those (put a long prybar on them, and see what movement there is), paying particular attention to the Pitman Arm, both at the linkage and at the gearbox. In rare situations, when everything checks out, I've had success increasing positive caster using Offset Ball Joints -- positive caster increases damping and steering stability. Caster is not adjustable on most stock TJ's, so these ball joints allow 'fixed' adjustments to be made. TSB#02-12-99 has part numbers (the parts department will know, as well as aftermarket steering/suspension OEM's) and more information, but bear in mind that these are only suggested, in the bulletin, for lead/drift issues.
If the Damper doesn't solve the issue, then I'd have it checked out by a reputable steering and suspension shop. If there are none near you, then maybe the dealer, since they are the last stop, and should take ownership of such a safety issue. I should warn you, though... they get touchy if the vehicle has a lift kit, since it alters all kinds of things. Still, I've driven in the Death Wobble, and it is very disconcerting.
Good luck to you!
