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The videos are kind of long at 18-19 minutes each. Hopefully, they are thorough enough to help.

Death Wobble Diagnosis and Inspection Jeep JK Wrangler Part 1 - YouTube
Death Wobble Diagnosis and Inspection Jeep JK Wrangler Part 2 - YouTube

Inspection Checklist is in Post #2.

I'll start out by explaining that Chrysler decided to use a 14 mm trackbar bolt, with a trackbar bushing sleeve designed for a 9/16" bolt, and the trackbar bracket bolt holes are somewhere around 15-16 mm large. This is a sure recipe for DW if the trackbar bolts are not properly torqued and periodically re-torqued to 125 ft. lbs.







Death Wobble is no mystery.
It is caused by loose bolts, damaged components, or improper
installation.

Look at the picture below and follow along:


First, the tie rod (green) has ends that attach to a knuckle on each side. As you could imagine, if either ends of the tie rod were broken or bad, that could be a culprit for a shimmy (not Death Wobble). A common place to damage the tie rod is on the driver's side at the adjusting sleeve (in the picture, just to the right of the red swaybar link). That sleeve (maybe not the correct term for it, but you can see what I am talking about) allows the width of the tie rod to be expanded or contracted. There are threads on that end that can be damaged, causing play on that driver's side and allow an up and down, or circular play movement. Again, this would cause a shimmy, not Death Wobble.

Next, look at the drag link (purple). On one end, it attaches to the pitman arm (lavender), that attaches to the steering gear box. On the other end, the drag link attaches to the passenger side knuckle. When you turn your steering wheel, a shaft turns that goes to the steering gear box. The steering gear box turns the pitman arm, and the pitman arm pushes or pulls the drag link, which pushes or pulls the knuckle. Your steering wheel is straitened by loosening the two nuts on the sleeve/turnbuckle on the drag link and rotating the sleeve/turnbuckle to lengthen or contract the length of the drag link. If either end of the drag link is damaged, this would cause a wobble or shimmy, but not Death Wobble.

Next, look at the trackbar (aqua). It attaches to a bracket on the frame on the driver's side and to the axle on the passenger side. The purpose of the trackbar is to center the axle on the frame. With the axle centered on the frame, it provides some resistance to the steering system to allow you to turn. If there was no trackbar and you turned the steering, the whole front frame would shift. As a result, there is significant force applied to the trackbar in driving and steering.

Now, imagine that the bolts that hold the trackbar are loose in their bolt holes, or that the bolt holes are wallowed out (oval), or that the bushings at the trackbar ends are damaged, or that the bracket at the axle side has come loose because the weld has broken, or that the bushings are all twisted up because the rig has been lifted without the installer loosening the bolts and then retightened them at the new ride height. All these things would allow play in the front trackbar. When you steer or go around a corner, these loose or broken things would allow the axle to shake or slide side to side. If you hit a bump in the road, it could knock the trackbar towards the driver's side. Then, the rest of the suspension (springs, etc.) would try to bring the trackbar back to the passenger side. If you were going at any sort of speed, you could develop a kind of harmonic resonance as the axle more and more violently slide/rocked/shaked from side to side. It would feel like your whole front end was being voilently torn apart. You would have to bring your vehicle to a complete standstill to stop the harmonic resonance. This is Death Wobble.

Even one incident of violent Death Wobble related to the front trackbar can cause significant damage. The voilent harmonic resonance of the back and forth shaking is more than the trackbar bushings, bolt holes, and brackets are designed to handle. A severe Death Wobble occurance can crack or break the welds on the axle side trackbar bracket, or the bolt can wallow out the bolt hole in the bracket, or the bushing can be permanently damaged.

This is the most common source of Death Wobble because inexperienced installers either do not remove the bolt from the trackbar when they install a lift--leaving the bushing pinched in the bracket and bound up, or they do not properly torque the bolts after the lift has been installed with the tires on and the full weight of the vehicle on the ground at ride height, or (maybe the most common) they do not retorque the trackbar bolts after the first 50 miles, after every heavy wheeling trip, and at every oil change interval.

Next, look at the lower control arms (purple) and the upper control arms (light blue). In the picture, they are aftermarket arms with a heim joint on one end. However, the stock control arms have a rubber bushing at each end. When the control arms are properly torqued, the bushing is somewhat pinched in the mounting brackets on the axle and the frame. Sometimes, an installer will make the mistake of not loosening the bolts for the control arms when they install a lift. What happens sometimes is they really bind up the bushings because they are pinched/sandwiched at stock ride height, but then forced to the new lifted ride height. These bound up bushings can cause weird handling, bushing failure, and lead to Death Wobble. The proper way is to loosen the bolts, install the lift, reinstall the wheels so the suspension and jeep are at the new ride height, rock the vehicle/suspension back and forth and side to side, then re-torque the bolts to spec, then after 50 miles re-torque them to spec, then after every oil change or very heavy wheeling trip re-torque them to spec.

Improperly balanced tires, too much air in tires, bent wheels, improperly installed wheel spacers, bad tires (with separated plys), and poor alignment specs (caster, camber, and not enough toe-in) can cause wobbles and shimmies that lead to Death Wobble. However, these precipitate Death Wobble, but they are not the cause of Death Wobble.
Although not specifically identified in the picture, the ball joints that are at the top and bottom of each knuckle where it attaches to the axle C can go bad. Bad ball joints can cause shimmies, wobbles, but usually not full on Death Wobble.

Next, allthough not identified in the picture, the unit bearings can go bad and be a cause of shimmy and wobble, but not Death Wobble.

Hope this helps--assuming you read it all.

Death Wobble is no mystery.

The reason that the steering stabilizer masks it is that it can absorb some of the side to side voilent harmonics of a loose trackbar or damaged mounts. However, this masking is dangerous because it will not prevent the eventual failure of trackbar bracket welds and bolt holes from trackbar Death Wobble.

It is extremely important to immediately diagnose and fix Death Wobble.

Even one episode of DW can damage other components.

Multiple episodes of DW are almost guaranteed to damage other components.






Multiple episodes will often damage your:

    • ball joints
    • tie rod ends--including the adjusting sleeve end on the driver side
    • trackbar bushings
    • trackbar bracket bolt holes
    • steering sector shaft (where the pitman arm attaches to the steering box)
    • steering stabilizer
    • front lower control arm bracket bolt holes
    • unit bearings
    • trackbar bracket welds
    • drag link ends
Hellbound13 is an example of a member who with 5-6 episodes of trackbar related DW on a stock jeep ended up "chasing his tail" for many, many months. He ended up replacing almost everything in the above list--sometimes more than once.


Without repairing/replacing everything that was damaged at once, the remaining damaged components continued to cause DW problems, further damaging the remaining components.


This is Death Wobble (and the guy is extremely foolish for repeating it on purpose):
YouTube - Death Wobble
 

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Discussion Starter #2 (Edited)
DIAGNOSIS CHECKLIST

Assuming your tire psi is 28-30, your tires/wheels have been balanced and rotated to make sure the wobble doesn't move with the rotation, here would be my order:


  1. Remove the steering stabilizer.
  2. Have someone turn the engine on and turn slowly from full lock to full lock while I visually, manually (with my hands on the components), and auditorily inspect for any play in the tie rod ends, drag link ends, sector shaft, trackbar ends/bolts/brackets, and trackbar bracket welds.
  3. Then, do the same thing but with short, sharp, quick back and forth turns of the steering wheel between the 10 o'clock and 2 o'clock positions, instead of the slow, lock to lock approach.
  4. Then, I would remove the front trackbar to inspect the bolt holes for ovaling and inspect the trackbar bushings for separation or cracking with a long screw driver through the bolt sleeve and the trackbar in a vise to leverage against the bushing in all directions. If all is good, I would reinstall the trackbar with the tires on the ground at ride height to 125 lbs.
  5. Then, I would inspect the drag link end joints by using a large channel lock wrench that gave me enough leverage to check for up and down play in the drag link ends. There should not be any meaningful up and down play. If there is, the ends should be replaced, or a new drag link with heavy duty joints should be installed. After, I would check the torque of the drag link ends. Taller lifts magnify the problems of bad drag link ends.
  6. Then, I would inspect the tie rod ends with the channel lock wrench for up and down movement. There should be no meaningful up and down play. There should only be rotational movement in the joint end.
  7. Then, I would put the front axle on jack stands with the tires about 2" off the ground and check the front ball joints by using a long pry bar as a lever under the front tires to lift them up to inspect for up and down play in the lower ball joints. There shouldn't be more than maybe 1-2 mm.
  8. Then, I would grab the top of the tire with both hands and push it towards the frame and pull it away from the frame to inspect for lateral movement of the top ball joints. There shouldn't be any.
  9. Then, I would remove the front tires/wheels and remove the front tie rod--one knuckle at a time. Then with a large wrench or vice grips, I would inspect the end for side to side play. Then I would reinstall the end and torque to spec and repeat on the other side.
  10. Then, I would remove the brake calipers and brake disks to inspect the unitbearings for play.
  11. Then, I would reinstall the discs, brake calipers, and tires/wheels and set the axle back on the ground.
  12. Then, I would support but not lift the front axle with a floor jack and loosen the front control arm bolts (upper and lower on the axle side). One at a time, I would drop the control arms to inspect the bolt holes and bushings (similar to with the trackbar), reinstall without torquing, and do the next one.
  13. Next, I would inspect the sector shaft that comes out of the steering box for cracking or twisting.
  14. Then, I would take a test drive without the steering stablizer to feel for any wobbles.
  15. Finally, I would reinstall the steering stablizer or spring $40 for a heavy duty steering stablizer.
If this front end inspection does not diagnose and/or solve it, then I would move to an alignment.

  1. I would use adjustable lower front control arms to set my caster spec between 4 and 5 degrees--with a cross caster that has less on the driver side than the passenger side. I would personally not do more or less, with a target around 4.5-4.7 degrees caster.
  2. If my camber is out of spec, but it is not due to failed ball joints, I would install offset ball joints to get my camber in spec.
  3. I would set my toe-in to spec on the machine--which is about a 1/16"-1/8" toe-in depending on tire size.
  4. If my front to rear alignment is off, I would install rear lower adjustable control arms to fix this.
Also, I recommend you switch out your stock 14 mm trackbar bolts for 9/16" grade 8 bolts.

See the following video for more information:

YouTube - Common Source of Death Wobble


With all this, I highly doubt you do not find the source.

The last ditch thing if there is a non-DW, speed dependent range wobble, I would borrow a different set of wheels and tires to see if it changes, and I would try driving it with no front driveshaft to see if that changes anything.

Although it is always a good idea to inspect your axle shaft u-joints, they will not cause DW.

The most common sources of full on DW are:

  • Improperly torqued trackbar bolts
  • Damaged trackbar and control arm bushings because bolts were torqued on a car lift or while the vehicle was not at ride height with the tires on the ground. When you torque trackbar and control arm bolts, the bracket pinches the bolt sleeve in the bushing, as well as the bushing itself. If this is at a geometry other than actual ride height, the bushings are twisted/bound/pre-loaded, and they will eventually fail/separate/etc. If you have a flex joint end, this does not apply for that end.
  • Ovaled out trackbar bracket holes due to DW episodes from loose bolts.
 

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wow!!! Thanks for the detailed description & photos.
 

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Discussion Starter #6
Glad to do it.:thumb:

I did a TJ version for their section as well.

I should add that inspection of the swaybar link bushings and proper torquing of swaybar link bolts should be included in the inspection list.
 

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Glad to do it.:thumb:

I did a TJ version for their section as well.

I should add that inspection of the swaybar link bushings and proper torquing of swaybar link bolts should be included in the inspection list.
Can we find the torque settings for all these things somewhere?
Did I see your Jeep in the competition on JF?
 

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Discussion Starter #9

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Thank you for the helpful information. Am I the only one that thinks this is clearly a recall item? I have an 08 JK Wrangler with no lift or anything. 38k miles and this started. This was my first jeep purchase and I'm so dissapointed in Jeep for not standing behind their product but rather having the consumer take care of it for them. I took my Jeep into the Jeep dealership today and their own staff is saying Jeep should do something about this don't you think they should? Sorry guys just venting.
 

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Discussion Starter #12
I do believe that jeep should at least do a TSB (Technical Service Bulletin) that instructs the dealer techs to weld washers over the trackbar brackets so that the trackbar bolts fit snuggly instead of having so much play from the factory.

I also believe that the Owners Manual should be updated to recommend re-torquing the front trackbar bolts to 125 ft. lbs. at every oil change interval and after every extended/vigorous offroading trip.

A very small percentage of JK owners will ever experience DW. However, that small percentage is sufficient to justify proper training of dealer techs and the addition to the Owners Manual.
 

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This forum is the best! Thank you so much for posting the info about this death wobble. My '07 Wrangler is stock with <22k on the machine. Had a DW experience today at about 45mph, I am so glad I was driving and not the wife, she would never drive it again.
I was at the bottom of a hill making a slight RH turn to start up the other side and hit a bump. This is a paved road, new pavement not a big bump at all. Sent that thing into a wobble that nearly took the wheel out of my hands. I slowly braked and slowed down to about 20mph then it ceased the wobble. It was kinda hard to get back up to the speed limit because of the fear of it happening again.
I just got the Wrangler I have put about 1,000 miles on it. It was certified used, with a 3 mo/3000 mile warranty so I am takling it in on Monday. They claimed they have had problems with the steering dampers. I will use the info provided on this forum to look at the front end myself and see if any of the problems shown here exist. I can only say that was a scary experience! thanks again. Dale
 

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"Death Wobble"?

Thank you very much for the information. I have been experiencing a front end vibration, mostly in the brake pedestal and not so much in the steering wheel, on my low mileage (16K) 2008 JKU Sahara. It only happens under firm braking from above 60 mph. I thought I had rotor(s) warped; but it doesn't always do it under similar conditions.

I use the Jeep as a daily driver; but only have a 9-mile commute to work in Orlando. to avoid a $1.50 in tolls in a 2-mile stretch on the Beach Line and my exit, I pop on and off the tollway near the airport. The problem mostly occurs when exiting the highway to an off-ramp/stoplight; though it does happen in the 55-mph stretch on Sand Lake Rd.

Front end alignment / tire wear is good and there is no problem under even 'panic' braking below 55 mph in rush hour traffic.

I'll have the dealer check the front end at my next oil change in a week or so and will post his findings.:confused:
 

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wobble

My daughter had a wobble start in her 07 Wrangler,stock jeep.Got burned by Firestone and the steering damper sale.Brought to me (30 year front end mechanic on cars to semi's).I put it on the alignment rack,lowered the caster from 7.0 degrees to 4.8 degrees,wobble gone.Of course I checked thr front end out and everything was tight.Jeep drives great and no wobble.I have written on other places in this forum and had others try the caster change after checking all the front end parts out.it does work if you can find a front end man that will think out of the box and try it.
 

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If not DW, then severe Shimmy

Thank you very much for the information. I have been experiencing a front end vibration, mostly in the brake pedestal and not so much in the steering wheel, on my low mileage (16K) 2008 JKU Sahara. It only happens under firm braking from above 60 mph. I thought I had rotor(s) warped; but it doesn't always do it under similar conditions.

I use the Jeep as a daily driver; but only have a 9-mile commute to work in Orlando. to avoid a $1.50 in tolls in a 2-mile stretch on the Beach Line and my exit, I pop on and off the tollway near the airport. The problem mostly occurs when exiting the highway to an off-ramp/stoplight; though it does happen in the 55-mph stretch on Sand Lake Rd.

Front end alignment / tire wear is good and there is no problem under even 'panic' braking below 55 mph in rush hour traffic.

I'll have the dealer check the front end at my next oil change in a week or so and will post his findings.:confused:
I called my dealer yesterday and scheduled an oil change and work on the Gas Tank Blow-back Recall and mentioned the "shimmy/wobble". She knew exactly what I was referring to; but argued it only happens when you hit a bump. I told her that was not the case with my Jeep.

BTW: I had an "excursion" on the way to work this a.m. at 60 mph under hard braking on the 6-lane near Florida Mall in traffic. If I let off the brakes and then re-apply gradually, no vibration.

I have invited her to take a test drive with me when I drop it off next week. I figure, if it "shimmies" severely when I brake hard at 65-70 mph as I hit the off-ramp from the Beachline, I plan to really impress her by making sure I'm doing at least 80-85 when I hit the brakes on the test drive. Should be really exciting! I should remind her to bring a change of underwear to work with her that day.

I really hate it when somebody who's never been in my vehicle contradicts me when I am describing an actual "happening", not a theoretical one.

As Poor Richard was quoted to have said, "Experience is a hard school; but a fool will learn by no other"....... :dance:
 

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Thanks planman. I am glad to see this shared here as well. :thumb:
 

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My daughter had a wobble start in her 07 Wrangler,stock jeep.Got burned by Firestone and the steering damper sale.Brought to me (30 year front end mechanic on cars to semi's).I put it on the alignment rack,lowered the caster from 7.0 degrees to 4.8 degrees,wobble gone.Of course I checked thr front end out and everything was tight.Jeep drives great and no wobble.I have written on other places in this forum and had others try the caster change after checking all the front end parts out.it does work if you can find a front end man that will think out of the box and try it.
How did you adjust/lower the caster in a stock jeep? And how on earth did a stock Jeep get to 7 degrees? 4.8 is still higher than the stock range (3.7 to 4.7)
 

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caster

You best look at a alignment spec book for 07 Jeeps.I just doubled checked on the Mitchell On Demand website and caster can go from 3.7 minimum to 8.0 degrees maximum depending on what model it is. Jeep uses high caster to force a model to drive straight and have steering wheel return. Jeep didn't have a major wobble problem years ago,it started when when Jeep put power steering and larger tires on their 4x4s. Now they created a handling problem and started to use caster with other angles to try and cure it. I have contacted the head alignment instructor for Hunter Engineering(alignment equipment designer and maker) Ron Freeman and we are putting a thread together for this forum. I hope that we can explain simply what caster wobble is and how it is caused. It is easier to cure if you understand how it is caused. You will also discover the largest Magnum steering damper WILL NOT cure Death Wobble, it will mask it until the damper gets worn. And worn parts in the front end just makes it worse,scarey worse. And again Jeep is not the only one that has this problem, when Chrysler bought Jeep they redesigned the Dodge pick-up and put a track bar on it. Guess what started to happen with Dodge pick-ups after that,worse after larger tires were put on it. I have driven a new 1990 Freightliner years ago at 50 mph and had death wobble start, the factory didn't tell me to put a steering damper on that. How about a Jeep that only has death wobble when he tows his fishing boat, figure that one out. There is alot more to Death Wobble than just caster but until now the threads I have been reading the most commn cure is throw a bunch of parts at it and pull your hair out. If they managed to cure it they don't know what they did or what caused it. Most of the alignment techs out there are doing the same thing for their customers, sell them parts and then blame Jeep for making a POS. Thanks for reading my rant.I hope I can send a informitive thread about caster soon.
 

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I am not doubting your knowledge, its just that you stated your daugters vehicle was a stock 2007 Wrangler. The 2007 JK doesnt have adjustable caster and specs are between 3.7 to 4.7 degrees (is there a 2007 TJ perhaps?).

Maybe Mitchel On Line is incorrect? Wouldnt be the first time, I stopped using them years ago due to wrong info.
 
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