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post #76 of 114 Old 06-28-2013, 10:27 PM
daddo
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post #77 of 114 Old 06-28-2013, 10:37 PM
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I start my suspension mod this week.
What part of Colorado are you in?...
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post #78 of 114 Old 06-29-2013, 01:31 AM
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...maybe 2-3 weeks would go by with no DW. Then when you wasnt ready it would do it's dance.

....

Completely gone.
This was just last week. I start my suspension mod this week.

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post #79 of 114 Old 06-29-2013, 07:48 AM
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If you want the quote to be attributed to the correct person, keep the quote tags intact or it fouls it up and makes it hard to follow.

If you want to reply to individual sections of a post instead of the whole thing at once, just type {quote} this part will be the part you are addressing and then close it off with {/quote} That will start and stop a quoted section.

Replace {} with [] to make it work.

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post #80 of 114 Old 12-28-2013, 07:42 PM Thread Starter
OzzLee
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I know this post is six months old....but the DW has stopped. While inspecting the front axle joints my step-dad noticed the front body mount was missing. We drilled a hole through a hockey puck and found a bolt that fit. Jeep hasn't done the Death Wobble since.
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post #81 of 114 Old 12-28-2013, 07:46 PM
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I know this post is six months old....but the DW has stopped. While inspecting the front axle joints my step-dad noticed the front body mount was missing. We drilled a hole through a hockey puck and found a bolt that fit. Jeep hasn't done the Death Wobble since.
Hockey pucks as body mounts not a good idea. If you do a search this is a good thread that discusses and has photos of what happens to hockey pucks under strong constant clamping force. Do yourself a favor and spend $5 and get a body puck made out of a material designed to handle that force.

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post #82 of 114 Old 12-28-2013, 08:01 PM
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Originally Posted by OzzLee View Post
I know this post is six months old....but the DW has stopped. While inspecting the front axle joints my step-dad noticed the front body mount was missing. We drilled a hole through a hockey puck and found a bolt that fit. Jeep hasn't done the Death Wobble since.
Then you never had Death Wobble in the first place. You had a vibe unrelated to the conditions that lend themselves to DW.
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post #83 of 114 Old 12-29-2013, 08:08 PM
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Originally Posted by OzzLee View Post
I know this post is six months old....but the DW has stopped. While inspecting the front axle joints my step-dad noticed the front body mount was missing. We drilled a hole through a hockey puck and found a bolt that fit. Jeep hasn't done the Death Wobble since.
Body mounts have as much to do with front end wobbles as the price of rice in Taiwan has to do with the outcome of the NFC East.

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post #84 of 114 Old 12-29-2013, 09:09 PM
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Body mounts have as much to do with front end wobbles as the price of rice in Taiwan has to do with the outcome of the NFC East.
Wobble by definition is vibration at some indiscernible frequency. If you understand that DW is happening at various frequencies depending on what happens to be the root cause of a particular manifestation, could one then make the case that altering the base rigidity of the attaching points could cause a change in frequency?

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post #85 of 114 Old 12-29-2013, 10:20 PM
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Originally Posted by mrblaine View Post
Wobble by definition is vibration at some indiscernible frequency. If you understand that DW is happening at various frequencies depending on what happens to be the root cause of a particular manifestation, could one then make the case that altering the base rigidity of the attaching points could cause a change in frequency?
Sure, one could. But the liklihood of that missing body mount being the root cause for his wobble is slimmer than slim.

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post #86 of 114 Old 12-30-2013, 08:04 AM
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Sure, one could. But the liklihood of that missing body mount being the root cause for his wobble is slimmer than slim.
Occam's Razor.

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post #87 of 114 Old 12-30-2013, 08:46 AM Thread Starter
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I didn't put a body mount in as a potential solution for DW, I put the body mount in because it was missing. We were originally under the Jeep looking for worn parts. I still have a brief (less than 2 seconds) shimmy when I hit a bump or pothole with one tire and not both. I'm inclined to agree with mrblaine about altering the base rigidity of the attaching points. When the mount was missing, the loose front end was able to move and bounce around exacerbating the root problem. Now that the front end is tight and secure, there is less to vibrate and the brief shimmy doesn't have a chance to snowball into full-blown death wobble.

That's the only logical explanation I can come up with. Like everyone has said, the front body mount should not have fixed DW.
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post #88 of 114 Old 12-30-2013, 09:19 AM
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Originally Posted by OzzLee View Post
I didn't put a body mount in as a potential solution for DW, I put the body mount in because it was missing. We were originally under the Jeep looking for worn parts. I still have a brief (less than 2 seconds) shimmy when I hit a bump or pothole with one tire and not both. I'm inclined to agree with mrblaine about altering the base rigidity of the attaching points. When the mount was missing, the loose front end was able to move and bounce around exacerbating the root problem. Now that the front end is tight and secure, there is less to vibrate and the brief shimmy doesn't have a chance to snowball into full-blown death wobble.

That's the only logical explanation I can come up with. Like everyone has said, the front body mount should not have fixed DW.
It is an easy test to sorta figure out what is going on. Remove the mount again and see what happens.

Precession is an evil thing and all it takes is some wear, alteration in the structure that affects frequency and stuff we don't fully understand can manifest itself in odd ways.

You are not the first person to report that a seemingly unrelated repair or alteration finally changed the stiffness of the structure enough to overcome the control of the front end components.

Now that doesn't mean that anyone can produce DW by removing a body mount when all their components that control the front end are new and in perfect condition, but it could easily point to upsetting that balance if something is not quite up to par normally but hasn't yet failed.

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post #89 of 114 Old 12-31-2013, 11:26 PM
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I still don't buy the precession thing... harmonics, resonance, un-dampened oscillation, make much more sense to me, and they also fall more in line with tightening and loosening various components allowing, or clearing up DW.
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post #90 of 114 Old 12-31-2013, 11:39 PM
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Hmm...I think if you removed precession from the equation, death wobble would be an entirely different experience...maybe less "deathly" lol. It would certainly not sustain itself and could probably be turned off as quickly as it comes on say, with a quick jerk of the wheel, or perhaps hitting the next bump in the road.

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