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-   -   The Importance of changing out stock bolts!! (http://www.wranglerforum.com/f274/the-importance-of-changing-out-stock-bolts-128154.html)

Djstorm100 12-17-2011 07:20 PM

The Importance of changing out stock bolts!!
 
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!!

http://img.photobucket.com/albums/v5...0/photo1-1.jpg






http://img.photobucket.com/albums/v5...00/photo-4.jpg


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.

eton 12-17-2011 07:47 PM

Quote:

Originally Posted by Djstorm100 (Post 1836611)
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!!

http://img.photobucket.com/albums/v5...0/photo1-1.jpg






http://img.photobucket.com/albums/v5...00/photo-4.jpg


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!)

eton 12-17-2011 07:48 PM

Do you have to jack the truck up to reduce force on the trackbar when you replace them?

Djstorm100 12-17-2011 07:51 PM

Quote:

Originally Posted by eton (Post 1836683)
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

Djstorm100 12-17-2011 07:53 PM

this actually needs to be one on all track bars and control arms.

deepbluewrangler 12-18-2011 11:02 AM

Quote:

Originally Posted by Djstorm100 (Post 1836693)
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:

ESP 12-18-2011 11:11 AM

Subscribed.

Djstorm100 12-18-2011 11:13 AM

Quote:

Originally Posted by deepbluewrangler (Post 1837897)
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

fm jump 12-18-2011 11:18 AM

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.

Djstorm100 12-18-2011 11:20 AM

Quote:

Originally Posted by fm jump (Post 1837933)
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.

ESP 12-18-2011 11:23 AM

Thinking the price is the same on the polyperformance site vs A.C.E?

Djstorm100 12-18-2011 11:26 AM

Quote:

Originally Posted by ESP (Post 1837943)
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.

ESP 12-18-2011 11:35 AM

Oh! Dustin are you coming today out with us?

Djstorm100 12-18-2011 11:37 AM

Quote:

Originally Posted by ESP (Post 1837964)
Oh! Dustin are you coming today out with us?


Naw Bud can't have to take my soildworks cert tests. Ya are going up to page road right?

Djstorm100 12-18-2011 11:39 AM

Heres a video of what I'm talking about too

Common source of death wobble on Jeep JK Wranglers - YouTube

kjeeper10 12-18-2011 12:07 PM

Awesome vid.

Wonder why it's that way??

Djstorm100 12-18-2011 12:12 PM

Quote:

Originally Posted by kjeeper10 (Post 1838031)
Awesome vid.

Wonder why it's that way??


One of those things the engineers didn't catch I rekon. From what I understand the TJ's are the same way?

Roadhawg 12-18-2011 12:30 PM

Good info... thanks

Sjeupie 12-18-2011 01:17 PM

Quite worrying...

j.luis 12-18-2011 01:31 PM

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

strider_mt2k 12-18-2011 01:39 PM

Makes me more determined than ever to learn the front end of my JK.
I never owned a vehicle that I wanted to fully "learn" before. -none have been worthy.
It's awesome.

MarkinOhio 12-18-2011 01:58 PM

Subscribed
 
Is this really true? Could something this simple really cause as much death wobble as everyone is having?

I find it hard to believe, would like to see some input from Jeep about this. If this is truly a big time fix for DW they should be ashamed of themselves.

I subscribed because just about every one I know who has lifted has had issues. I really want a lift, but really don't want to deal with DW and its related problems.

Terex 12-18-2011 02:39 PM

Jeep should issue a TSB on this matter. Both Jeep and NHTSA should be advised.

j.luis 12-18-2011 03:19 PM

Quote:

Originally Posted by terex (Post 1838367)
jeep should issue a tsb on this matter. Both jeep and nhtsa should be advised.

+1

The C People 12-18-2011 03:28 PM

Interesting and subscribed.

Djstorm100 12-18-2011 03:54 PM

Quote:

Originally Posted by MarkinOhio (Post 1838256)
Is this really true? Could something this simple really cause as much death wobble as everyone is having?

I find it hard to believe, would like to see some input from Jeep about this. If this is truly a big time fix for DW they should be ashamed of themselves.

I subscribed because just about every one I know who has lifted has had issues. I really want a lift, but really don't want to deal with DW and its related problems.


The numbers don't lie, common sense is well common. Proof if proof.

I've been wrenching for nearly 10 years and when I saw this I was actually shocked, not what I found but during the install how the bolts aren't shoulder.

The problems are:
  1. The holes for the track bar and the bracket are 9/16 while they use a 14mm bolt which is smaller. This causes a clearance issue of .0114
  2. the bolt is not shoulder, thus causing the load to be put on the threads, image walking on razor blades that are vertical (extreme I know but this is to show my point) Now add twisting from the axle going up and down on the track bar and control arms. You have the threads now cutting in to the sleeve because of Problem number 1
  3. The clearance over time can make the hole like a oval and you can experience death wobble or even before that. As movement is easy through this.
  4. Since the size of the holes are off, once you tighten the bolt down it clamps on to the sleeve to hold it in place but the bolt can still move in/around the holes because of the clearance above, this over time will cause damage.
  5. The TQ is implied through the head of the bolt, the bolt will twist due to friction first and then start to turn. So after it is said and done with you really might not have 125/150 lbs where it should be. AT THE NUT! But in this application is hard to do so. But because of problem 2 with the threads will cause more friction and more friction means more inaccurate tq read out.
The dealers will be pointless to go to. Why? They sell and fix cars, not engineer them. They will blow you off as if you are the person saying the world is going to end on Christmas.


All in all it is a design flaw, I think the TJ are the same way and while there are hundreds of thousands of jeeps on the road (JK and TJ) I personally feel a lot of the DW could be avoid by using the right size bolts. Sorry if I sound like I'm repeating my self I have two threads going on.


WATCH THE VIDEO! IT SPEAKS FOR IT SELF IN THIS MATTER.

Keep Moving Forward 12-18-2011 03:56 PM

Subscribed.

1SAS 12-18-2011 05:23 PM

Dustin,

Thanks again for the information. You have helped a lot of people, especially jeepers. I only hope fellow jeepers get off their butts to get the word out. It is a simple and easy fix that anyone can do. Thanks again. And please, thank your dad too. I see he helped.

Take care,

eton 12-18-2011 07:00 PM

Quote:

Originally Posted by Djstorm100 (Post 1837969)
Naw Bud can't have to take my soildworks cert tests. Ya are going up to page road right?

Good luck with the test, we'll catch you next time around.

NFRs2000NYC 12-18-2011 07:09 PM

So the consensus is, for all Jeep owners to do this? I just picked up my '12 JKU Sahara, and would like to avoid these issues. I should replace these on my own, or let the warranty handle it? I like to stop problems BEFORE they actually happen.

On a side note, on a stock rig, how many of these bolts does one need to purchase/replace? Do you need an alignment or anything of that nature after replacement?


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