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Topic Review (Newest First)
08-19-2014 06:24 PM
Whiskerfish That bracket (axle end) for the Track bar on my Wife's 05 is junk. I think the door panels are made from heavier gauge that that thing is (being factious). Anyway I welded a small plate on it and line reamed it up to the next size and things have been good for me for a good long while now. The most challenging part was Drilling out the bushing on the track bar to the next size. That was no joke, those bushings are some seriously hard stuff.
08-19-2014 02:01 PM
BirminghamTJ
Quote:
Originally Posted by jnukes View Post
I have read a lot of forums about the Death Wobble. I experienced it a couple times after placing a 2 in budget boost. I hear this quite frequently in the forums. I believe that it is also prevalent in the higher lifts, however not as many of those are on the road. Prior to placing the BB on my '05 LJ I had a slight shimmy right at 55mph. I have been chasing this issue for a couple of years now. I have new upper and lower ball joints, steering ball joints, control arm bushings, new tires, steering stabilizer, and probably something else I forgot. I have not gotten the true DW since the stabilizer, but continue to get the shimmy at 55 mph. Next on my list is to try a new adjustable track bar. I will report the results.
I would be willing to bet that the frame or axle side track bar bolt has worn out its bracket. I'd check it and if it is drill it out to 1/2" grade 8 minimum or weld new brackets on.
08-19-2014 01:22 PM
jnukes
DW continued

I have read a lot of forums about the Death Wobble. I experienced it a couple times after placing a 2 in budget boost. I hear this quite frequently in the forums. I believe that it is also prevalent in the higher lifts, however not as many of those are on the road. Prior to placing the BB on my '05 LJ I had a slight shimmy right at 55mph. I have been chasing this issue for a couple of years now. I have new upper and lower ball joints, steering ball joints, control arm bushings, new tires, steering stabilizer, and probably something else I forgot. I have not gotten the true DW since the stabilizer, but continue to get the shimmy at 55 mph. Next on my list is to try a new adjustable track bar. I will report the results.
07-25-2014 08:39 PM
Majnoon ^^ cool post!
07-25-2014 08:35 PM
44 Echo Death Wobble, for anyone who cares, is technically Harmonic Resonance. Everything that moves, hence rotates, resonates or vibrates as it moves. For this many vehicles, of a certain brand and type, including my TJ recently, this is an inherent design flaw. The total system was designed at or near its Harmonic Frequency, a point at which the vibration moves throughout the system, repeating itself at the exact same time the next vibration occurs, thus building on itself. As each vibration occurs it leaves a little bit of itself behind. Just one vibration eventually dissipates, getting fainter in time until ends. Normally, the vibration, or frequency, is offset so by the time the "leftover" shock of the initial wave starts to return, the next wave of energy slams into it from the opposite direction, thus canceling it. If, however, the first wave matches exactly the first, again they build on one another, growing in intensity. Engineers know this, and so they are supposed to test their designs so they know where the nodal point is, that point where the frequencies exactly match one another. Changing the mass, size, or shape of just one component can alter that frequency nodal point. One other point, as most point out, changing out a steering damper most likely is only masking the problem. With this much vibration, if you don't address the issue immediately, you're just wearing out parts. It is quite conceivable that if continued to drive, something could literally fail. Google the Tacoma Narrows Bridge, if you want to see Harmonic Resonance to the point of total failure. Imagine that being your front end.
02-23-2014 07:30 AM
BusinessRogue
Quote:
Originally Posted by DoubleOught View Post
A lot of things can contribute to DW but the track bar is the single most important item to prevent it. Also check your unit bearings and make sure they have no play. If a new stablilizer "fixed" it, you probably have other problems that you are not aware of.
Read back a few posts. I've replaced everything except the drag link, although I replaced its tie rod.

I know for a fact tires without any weights (completely unbalanced) will cause the vehicle to start DW at extremely low MPH.
02-23-2014 07:24 AM
DoubleOught A lot of things can contribute to DW but the track bar is the single most important item to prevent it. Also check your unit bearings and make sure they have no play. If a new stablilizer "fixed" it, you probably have other problems that you are not aware of.
02-23-2014 07:17 AM
BusinessRogue Update! Got my tires balanced. Death wobble gone. Now, I didn't have any weights in the tires because the idiot who flipped them (even out the wear) took out the weights. This can make a vehicle DW at 15MPH in 2WD with the right bump.

Waiting on my alignment until my new rear adjustable track bar comes in to center the axles.
02-18-2014 07:19 PM
BusinessRogue
Quote:
Originally Posted by Hewillfly View Post
no worries mate - keep us updated... I'm curious to see if that stuff actually works! I plan to be buried in this jeep, anything helps to keep it running !
I'll know more tomorrow, going to get my tires re-balanced and have an alignment done. I'll update then. I just want it to be 100% before I take it on a trip and get 300 miles away from home.
02-18-2014 07:16 PM
Hewillfly
Quote:
Originally Posted by BusinessRogue View Post
Thanks for the advice I greatly appreciate it my man.
no worries mate - keep us updated... I'm curious to see if that stuff actually works! I plan to be buried in this jeep, anything helps to keep it running !
02-18-2014 05:28 PM
BusinessRogue
Quote:
Originally Posted by Hewillfly View Post
Check the condition of your transmission.... I thought I had DW too. I got had to replace my torque converter because it tc lock up issues... Anywho no more DW afterwards. I later found out about a friction modifier that fixes that sort of shudder problem, it's called Dr. Tranny - google : " dr tranny jeep tj" you'll see what other people are saying. I don't know if it's snake oil but it's worth a shot before spending 1500 to have ur tc replaced. IMHO
Thanks for the advice I greatly appreciate it my man.
02-18-2014 05:23 PM
Hewillfly Check the condition of your transmission.... I thought I had DW too. I got had to replace my torque converter because it tc lock up issues... Anywho no more DW afterwards. I later found out about a friction modifier that fixes that sort of shudder problem, it's called Dr. Tranny - google : " dr tranny jeep tj" you'll see what other people are saying. I don't know if it's snake oil but it's worth a shot before spending 1500 to have ur tc replaced. IMHO
02-18-2014 03:39 PM
BusinessRogue
Quote:
Originally Posted by rubiconvict05 View Post
By the way replacing your steering stabilizer will only mask any problem. I'm not saying that it wasn't a bad choice but a S.S. won't correct the problem at hand.
The strut no longer had pressure so I replaced it. About page 14 I noticed the trend. Lol

Although I could have 6 and mine would probably get worse.
02-18-2014 03:09 PM
rubiconvict05 By the way replacing your steering stabilizer will only mask any problem. I'm not saying that it wasn't a bad choice but a S.S. won't correct the problem at hand.
02-18-2014 03:07 PM
rubiconvict05 I have finially tracked down the source of my death wobble. Now I know there are 92 pages to this thread so forgive me if this has been covered.
I needed to replace my front u joints, during the disassembly I removed the front hubs both had a dried mud ring that disallowed me to feel wheel bearing wobble with the standard shake test. I replaced the wheelbearings and boom wobble completely gone. Prior to this discovery I had replaced all steering linkage, all ball joints, track bar, pitman arm, tires, had the rims checked for trueness, checked all bolts and nuts for tightness from steering wheel to steering box for tightness, and controll arm bushings and bolts for correctness. I then had two alignments. After replacing the wheelbearings I then had another alignment. This was a long fought battle where I didn't throw parts at it but replaced everything that had even the slightest amount or wear.
02-18-2014 01:36 PM
BusinessRogue WELL!

I've changed my :

Track Bar
Tie Rod End (of drag-link)
Steering Stabilizer
Power Steering Gear (the whole thing)

Now, the DW starts at 30MPH. I'm thinking tires...balancing/alignment? Anyone have any ideas?
02-15-2014 01:17 PM
BusinessRogue
Quote:
Originally Posted by Shark_13 View Post

It will rotate a bit since there are tie rod ends on both sides, but should be stiff if trying to rotate by hand.
I would check bolt tightness on both ends with a torque wrench first. Then check them for slop during the dry steer test.
Got it thank you.
02-15-2014 01:16 PM
Shark_13
Quote:
Originally Posted by BusinessRogue View Post

Good information. So I have a question. Last night I was adjusting my steering wheel to center, and that whole drag link bar could move...I'm guessing it should be stiff and not move unless I turn the steering wheel, right?
It will rotate a bit since there are tie rod ends on both sides, but should be stiff if trying to rotate by hand.
I would check bolt tightness on both ends with a torque wrench first. Then check them for slop during the dry steer test.
02-15-2014 01:07 PM
BusinessRogue
Quote:
Originally Posted by kjeeper10 View Post
The bigger issue with DW is the harm it does to every part in your front end.
Let's say you have a loose track bar bolt and experience DW. Once ... Twice .... Whatever.
Easy fix right ? Tighten the loose bolt. Wrong !!
The DW kills ball joints, tie rod ends, control arm bushings. Ruins steering box. Wallows track bar holes, and in some cases rips the track bar right of the jeep.
It's very important to do a 100% inspection. I mean everything. Pull of the track bar (#1 cause for DW) and inspect the holes for wear/ovaling, then inspect the welds. Then on to the Track bar TRE. Then ball joints. Then inspect the other TRE's. Control arm bushings and mounts, lastly the pitman arm where it goes into the steering box, the dry steer will reveal any play.
I'm sure I missed something ... Check everything !!!!!!!
Good information. So I have a question. Last night I was adjusting my steering wheel to center, and that whole drag link bar could move...I'm guessing it should be stiff and not move unless I turn the steering wheel, right?
02-15-2014 12:58 PM
kjeeper10 The bigger issue with DW is the harm it does to every part in your front end.
Let's say you have a loose track bar bolt and experience DW. Once ... Twice .... Whatever.
Easy fix right ? Tighten the loose bolt. Wrong !!
The DW kills ball joints, tie rod ends, control arm bushings. Ruins steering box. Wallows track bar holes, and in some cases rips the track bar right of the jeep.
It's very important to do a 100% inspection. I mean everything. Pull of the track bar (#1 cause for DW) and inspect the holes for wear/ovaling, then inspect the welds. Then on to the Track bar TRE. Then ball joints. Then inspect the other TRE's. Control arm bushings and mounts, lastly the pitman arm where it goes into the steering box, the dry steer will reveal any play.
I'm sure I missed something ... Check everything !!!!!!!
02-15-2014 12:45 PM
BusinessRogue
Quote:
Originally Posted by Shark_13 View Post

Just like how it sounds, you hit a bump and the Jeep steers by itself.
This happens because the track bar and drag link are not parallel anymore ( drag link is too low due to the dropped Pitman arm)
Start by replacing it, reset your alignment (toe in), then do the dry steer test , if you just experienced death wobble you will see something moving that shouldn't be.
See above. I thought I was going to be killed by my TJ.
02-15-2014 12:41 PM
Shark_13
Quote:
Originally Posted by BusinessRogue View Post

What exactly is bump steer?
Just like how it sounds, you hit a bump and the Jeep steers by itself.
This happens because the track bar and drag link are not parallel anymore ( drag link is too low due to the dropped Pitman arm)
Start by replacing it, reset your alignment (toe in), then do the dry steer test , if you just experienced death wobble you will see something moving that shouldn't be.
02-15-2014 12:32 PM
BusinessRogue OK folks. I thought I had experienced death wobble, until today. Now, our roads here are due to all the semi traffic hauling grain every single day.

Here I am, driving home after another unsuccessful adventure into Advanced Auto Parts...and out of no where my steering wheel is violently going back and forth so fast it's almost a vibration, but it feels like the TJ is going throw itself left and right for miles so I slam it into 4WD and it slowly stops.

I honestly thought I was going to die. Now, I just fixed my steering wheel and got it all centered and re-tightened the but on the drop pitman arm but that was it. Why the did my TJ do that NOW, but never before?

Note: there's always been a slight shimmy in the wheel when I hit a bump but this time, I thought I was going to die since it did it as 62mph.
02-15-2014 09:15 AM
BusinessRogue
Quote:
Originally Posted by kjeeper10 View Post
With the TJ's type y steering it does more harm them good it seams. Unless you separate the drag link and tie rod and raise the track bar like the JK. You're essentially lowering front center of gravity or roll center. On a JK or a true high steer set up. The drag link is raised over the knuckle and the track bar is raised. This raises the front roll center and take a lot of stress off the steering box-unlike a DPA.
Thank you for the explanation.
02-15-2014 09:14 AM
BusinessRogue
Quote:
Originally Posted by Shark_13 View Post

I think they were quite common with earlier Jeeps, they were actually needed with a lift. But on TJ's they generally cause bump steer.
Luckily you can find a new stock one for under $30, or maybe score a used one. I got lucky and found one free on craigslist.
What exactly is bump steer?
02-15-2014 08:40 AM
Shark_13
Quote:
Originally Posted by BusinessRogue View Post

Question, why would the previous owner install a dropped pitman arm, if its going to cause all these issues? Because of the lift?
I think they were quite common with earlier Jeeps, they were actually needed with a lift. But on TJ's they generally cause bump steer.
Luckily you can find a new stock one for under $30, or maybe score a used one. I got lucky and found one free on craigslist.
02-15-2014 08:03 AM
kjeeper10 With the TJ's type y steering it does more harm them good it seams. Unless you separate the drag link and tie rod and raise the track bar like the JK. You're essentially lowering front center of gravity or roll center. On a JK or a true high steer set up. The drag link is raised over the knuckle and the track bar is raised. This raises the front roll center and take a lot of stress off the steering box-unlike a DPA.
02-15-2014 07:23 AM
BusinessRogue
Quote:
Originally Posted by wwch99tj View Post

Some lifts include them in the "package" so people install them thinking they're necessary
you should only install one if you have a drop track bar mount also
I don't, so that's good to know. Man, I'm learning a ton about how all this works. Thanks for all the help.
02-15-2014 07:19 AM
wwch99tj
Quote:
Originally Posted by BusinessRogue View Post

Question, why would the previous owner install a dropped pitman arm, if its going to cause all these issues? Because of the lift?
Some lifts include them in the "package" so people install them thinking they're necessary
you should only install one if you have a drop track bar mount also
02-15-2014 07:14 AM
BusinessRogue
Quote:
Originally Posted by Shark_13 View Post

Stock vs dropped Pitman fyi
Question, why would the previous owner install a dropped pitman arm, if its going to cause all these issues? Because of the lift?
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