I have a problem that I have never seen anything like. It is a 99 Cherokee sport 4.0l with stock up-country package. No lifts. Jeep has over 200,000 miles on it. About a year ago I was going down a secondary road about 60 mph and there was a place in the pavement that was "wavey" (sort of like a wash board). When I hit that the entire jeep began to shake. I do not exaggerate when I say that I would not have been at all surprised if all 4 wheels had came off and all the doors too! I pulled over, looked under the front end, everything intact. Took off and everything was fine. I had ran the tires bald to the bands when this happened, so I got new ones. About 6 months later was on the interstate, 65 mph, came upon a wavey place in the pavement. Same thing. My teen daughter and her friend screamed (thought they were going to die). Again pulled off, looked underneath, nothing amiss, went on. Third time about two weeks ago. Same details but I was paying more attention. Taking it out of gear makes no difference. Braking makes no difference. The shake stays there until the vehicle comes to a complete stop, then when I start driving again it is all fine. At normal times the steering feels fine (no pull or apparent play), the brakes are good (no wobble or noise when braking), the jeep rides smooth, tire wear seems even. I can't exaggerate how bad this thing shakes when it happens. How nothing flies off I have no idea. Does anyone have an idea of what this might be? Why does it only do it when hitting bumpy pavement at 60 plus? Why does it continue all the way to a complete stop then go completely away? What parts might I look at (am a beginner). Thanks again as the answers I get here are always right on.

Neven

 

It's the dreaded DEATH WOBBLE.

 

Slow down?

 

Death wobble reigns once again and I think it possessed your jeep!

Time to perform an exorcism!

All kidding aside, Its time to check all your steering components one by one. I have the same death wobbles as you, and I found couple causes of it...

Check all bushings, I mean ALL of them... Control arm ends (both ends and all four arms)
Tie rod ends
Track bar bushing
Any play in steering box?
Sway bar end links bushings
Drag link and pitman tie rod end
Ball joints (lowers and uppers)

Note that I didn't include steering stabilizer on the list because it have nothing to do with the cause of the wobbles. Yes replacing it probably would stop it, but only temporarily, and its considered a "bandaid".

A properly set up steering system doesn't need a stabilizer.

When I had the wobbles and me being a newbie, first thing I did was to replace the stabilizer (before I ever thought of joining the forums). It stopped the wobbles and I was ecstatic, but that didn't last long because six months later I got it again. I replaced all tie rods and I'm about to replace the control arm bushings because visual inspection showed that the rubber bushings are severely cracked.


Good luck o you, in the quest to find out the cause.

 

You have worn front suspension parts.

Get under the jeep,and have a buddy shake the steering wheel back and forth quickly.You'll easily be able to identify worn steering components

Your tie rod ends and/or control arm bushings are probbably shot .

Here is a good picture of the possible culprits

 

Beautiful picture. I'm gonna save that on my photo album

 

Wow, thanks. Especially the great picture!!!! I'll crawl under there this weekend after work.

 

Yep, I did the same thing first time it happened. Thought sure I'd find the front suspension somewhere in the ditch behind me.
Here's more info for you:
http://www.allpar.com/SUVs/jeep/death-wobble.html

 

How much play is in your steering wheel?

 

In normal driving I don't notice any. do you mean that or when sitting still or with the jeep up on jack stands with someone turning the wheels (haven't done that yet). Being a beginner when I do jack it up and put it on stands and have someone turn the wheel I am not sure I will recognize what I should be looking for. I did jack up one side at a time yesterday and checked for movement in the wheel. I notice that the tie rod moved with the steering knuckle so maybe the tie rod end is OK. How would I check for play that I might not be noticing?

 

This is most definitly the "death wobble" best thing to do is get to a tire shop and have the front end checked out. Usually ends up only being a few hundred bucks.

Scares the bejesus out of you doesn' it