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Discussion Starter #1
Everyone here on the forums has heard or has experienced death wobble. Most of the time it is due to track bar bolts not being tight enough and causing damage. Most people DON'T know is that the bolt is a 14mm but the whole for the track bar and bushing is 9/16. Thus we have a small clearance issue. The track bar only stays in place due to a clamping force on the sides BUT the REAL problem is that the bolts are completely threaded to the head vs using shoulder bolts to contact the area of the bushing only. Doesn't sound like a big deal right? I'll let the pictures do the talking. I installed my lift kit and track bars, I've done everything my self and tq them to spec. My lift kit and track bar has less than 1,500 miles on it!!











Notice the thread were "eating" in to the metal sleeve in the bushing. Now I'm not hard on my jeep and have only taken it off roading once since I've had it. I know its a crime, but the importance I'm trying to show here is that it is a very good idea to change out the bolts on the control arms and track bars to shoulder bolts to prevent damage and to also avoid death wobble.
 

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Everyone here on the forums has heard or has experienced death wobble. Most of the time it is due to track bar bolts not being tight enough and causing damage. Most people DON'T know is that the bolt is a 14mm but the whole for the track bar and bushing is 9/16. Thus we have a small clearance issue. The track bar only stays in place due to a clamping force on the sides BUT the REAL problem is that the bolts are completely threaded to the head vs using shoulder bolts to contact the area of the bushing only. Doesn't sound like a big deal right? I'll let the pictures do the talking. I installed my lift kit and track bars, I've done everything my self and tq them to spec. My lift kit and track bar has less than 1,500 miles on it!!











Notice the thread were "eating" in to the metal sleeve in the bushing. Now I'm not hard on my jeep and have only taken it off roading once since I've had it. I know its a crime, but the importance I'm trying to show here is that it is a very good idea to change out the bolts on the control arms and track bars to shoulder bolts to prevent damage and to also avoid death wobble.
Great find Dustin - Thats next up for me (after tomorrow of course!)
 

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Discussion Starter #4
Do you have to jack the truck up to reduce force on the trackbar when you replace them?
Thank you! Nope! I use a big screw driver to pull the track bar back to the mounting holes, it was very close to start with but just need a slight nudge
 

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this actually needs to be one on all track bars and control arms.
Very, very interesting. I have a few questions, as I am getting new drag link, track bar and tie rod with all new ends in January. (Rock Krawler, opinions welcome) Thinking about the JKS front trackbar and sector shaft reinforcement kit (pn#OGS166). I am just starting to get the slightest wobble and decided to beef up all the steering before it becomes a reel issue.
  1. Do you have a picture of the old bolts and the new bolts?
  2. Do you have a source for the new bolts?
  3. Which size did you use 14mm or 9/16"?
  4. Which track bar is that in your picture?
Thanks for any info.:wavey:
 

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Discussion Starter #8
Very, very interesting. I have a few questions, as I am getting new drag link, track bar and tie rod with all new ends in January. (Rock Krawler, opinions welcome) Thinking about the JKS front trackbar and sector shaft reinforcement kit (pn#OGS166). I am just starting to get the slightest wobble and decided to beef up all the steering before it becomes a reel issue.
  1. Do you have a picture of the old bolts and the new bolts?
  2. Do you have a source for the new bolts?
  3. Which size did you use 14mm or 9/16"?
  4. Which track bar is that in your picture?
Thanks for any info.:wavey:
its been know that rock krawler bushings are 14mm so you'll need to drill them out to 9/16.

The stock bolts look stock lol Its because they are thread all the way up to the head (part the socket grabs). Poly performance sells a kit to replace all lower control arm bolts and the track bars front and rear. You can also go to the local hardware store and get them there too. Just measure the width of the brackets so know who much shoulder(smooth area) you need.

My track bar is the JKS and I love it.

The bracket holes and the control arms/track bar holes are 9/16 but the bolt is 14mm.

14mm=0.5511"
9/16" =0.5625"

as you can see that .0114 does make a difference and a big one at that. Everything has been tq like it should and has been check. This is not install error of why this happen. Also combine the fact that the track bar bushing rides on the threads of the bolt, meaning less surface are and thus the threads act as teeth cutting in to the bushing when you start to flex or driving around on.


http://www.polyperformance.com/shop/...t-p-28601.html
 

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Just what I was looking for. Thanks for sharing. I wonder if the new Rubis have this problem. Ill do this as soon as I ge my jeep.
 

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Discussion Starter #10
Just what I was looking for. Thanks for sharing. I wonder if the new Rubis have this problem. Ill do this as soon as I ge my jeep.

It effects all jeeps because they don't have shoulder bolts stock. I'm surprised the engineers did this. Common sense goes along way, when you have something with movement on a axis (center/circumference of a bolt) it needs to ride on something smooth but fine threads.


If you go to the hardware store, ace's will be your best be. Make sure you get FINE THREADS or it will say UNF.
 

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Discussion Starter #12
Thinking the price is the same on the polyperformance site vs A.C.E?

eh not really, its just convenience with going with the poly. I like their washers are they are nice and thick. They are about the thickness of two washers stacked.. Grade 8 bolt will be around 3-4 bucks in that range I would think. Then add the washers and nuts. It be close even after burning gas if one place doesn't have enough or all your bolts.
 

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we should be able to take them back to the dealership and have them replace the bolts now that this is coming to light...
 
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