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Jeep&dogs

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So I’m actually out in the shop now. My Jeep from the ground to the center of the track bar bolt passenger side and ground to the passenger drag link passenger side is 1/4” different. Track bar is higher. Driver’s side is also 1/4 different, track bar is higher.
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Terminex

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That is very interesting what brAcket do you have? Mine was rasied almost 3” with my flip.

*edit* answered my own question (teraflex) lol
yeah, Teraflex offers 2 different front brackets based upon the height of your lift.
 

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So I’m actually out in the shop now. My Jeep from the ground to the center of the track bar bolt passenger side and ground to the passenger drag link passenger side is 1/4” different. Track bar is higher. Driver’s side is also 1/4 different, track bar is higher.
yours is about perfect then since they are perfectly parallel.
 

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That’s why I can’t figure out how yours measure equals with a raised mount.
I am right with you. We must be measuring different locations.

Angle isn't the best due to the front bumper ski hanging down so far, but check out the attached picture. my Drag link & track bar are almost perfectly aligned.

Jeep Wrangler JL BUMP Steer 20210318_151650
 

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I am right with you. We must be measuring different locations.

Angle isn't the best due to the front bumper ski hanging down so far, but check out the attached picture. my Drag link & track bar are almost perfectly aligned.

20210318_151650.jpg
Thanks for pic Matt. What height lift are you on, and did you center your axle with track bar or is it same length as factory ? If your track bar is a little short, then that would explain why the bracket helped.
 

XxsullyxX123

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Gotcha. Maybe try taking a look at the ball joints. I have read on here that some are reporting under torqued and loose castle nuts from the factory. After replacing their entire steering they still had issues but tightening up the ball joints fixed it.
Warning, taking out the cotter pins is most likely going to be a PITA.
had a look at the ball joints for fun. 1 of the 2 cotter pins was a bitch. With cotter pins, it always seems if you don’t get the perfect “bend back to straight” on the first try you are stuck messing with it forever lol. Anyhow, the torque was fine. I was able to nudge the bottom to get it at 35lbs but not even enough to change the slot the cotter pin was through so I’m sure it was fine. Top joint was a total pain to get the right angle to get a torque wrench on with an articulating extension with the axel still there. In any event, I checked just the side that seems to initiate the shimmy on impact as to not create extra work yet. And my bump steer/ shimmy may even be excessive to say 1-2 seconds. It’s more like 2-3 shimmy’s of the wheel that takes place in under 1 second (and never a death wobble scenario).
 

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Thanks for pic Matt. What height lift are you on, and did you center your axle with track bar or is it same length as factory ? If your track bar is a little short, then that would explain why the bracket helped.
Rancho 2.5 / 3.5” lift. (2.5 on Rubi / 3.5 on sahara)

axle is centered using the frame rail to tire for measurements.
 

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had a look at the ball joints for fun. 1 of the 2 cotter pins was a bitch. With cotter pins, it always seems if you don’t get the perfect “bend back to straight” on the first try you are stuck messing with it forever lol. Anyhow, the torque was fine. I was able to nudge the bottom to get it at 35lbs but not even enough to change the slot the cotter pin was through so I’m sure it was fine. Top joint was a total pain to get the right angle to get a torque wrench on with an articulating extension with the axel still there. In any event, I checked just the side that seems to initiate the shimmy on impact as to not create extra work yet. And my bump steer/ shimmy may even be excessive to say 1-2 seconds. It’s more like 2-3 shimmy’s of the wheel that takes place in under 1 second (and never a death wobble scenario).
Well, the shimmy you are describing I have been fighting for the last 3-4 months. I have replaced everything on the front end at least once and a few parts twice. Tires, wheels,ball joints, tie rods, drag links, steering boxes. I probably have spent 5-6k trying to fix it and literally 100’s of hours. I honestly thought I found the problem and just swapped that part out and took it for a drive.....still there. Hopefully one of these days someone figures out the cause, but I am out of ideas and patience at this point.
 

XxsullyxX123

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Well, the shimmy you are describing I have been fighting for the last 3-4 months. I have replaced everything on the front end at least once and a few parts twice. Tires, wheels,ball joints, tie rods, drag links, steering boxes. I probably have spent 5-6k trying to fix it and literally 100’s of hours. I honestly thought I found the problem and just swapped that part out and took it for a drive.....still there. Hopefully one of these days someone figures out the cause, but I am out of ideas and patience at this point.
Wow, that’s brutal. honestly, i really only notice it if i hit this exact same spot on the same road at just the right constant speed (30-40mph) while not under acceleration. I travel the road frequently, which is why I notice it, but frankly it may use be the perfect angle that hits the right tire before the left just enough to throw the axel for a second. It’s not every bump, and I can’t say I’ve felt it on other roads. So maybe its just a fluke on that one spot. Once I start commuting to work more and drive more, I will see I presume


EDIT: I just read one of your front end shimmy threads with the poll in it. Sounds strangely familiar to what I just wrote. I have a solution for us

Take a different road hah
 

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Resurrecting this thread. I posted my similar issues with a brand new Metalcloack lift/steer kit. I'm not hopeful of mitigating my shimmy/bumpsteer, but feels like track bar relocation is as cheap a place to start after tire pressure and messing with more alignment. A response I got was:

Honestly, if its not killing you, then live with it, There just isn't enough knowledge out there for JL yet as to how best to mitigate this,.........You may want to just play around with the parameters that are tunable, Ie, Tire pressures, castor, even camber ( with Adjustable ball joints ) wheel offset ( scrub radius ) toe setting. All these are things you can experiment with, hey, maybe you'll be the one that figures it out.
 

Jeep&dogs

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Resurrecting this thread. I posted my similar issues with a brand new Metalcloack lift/steer kit. I'm not hopeful of mitigating my shimmy/bumpsteer, but feels like track bar relocation is as cheap a place to start after tire pressure and messing with more alignment. A response I got was:

Honestly, if its not killing you, then live with it, There just isn't enough knowledge out there for JL yet as to how best to mitigate this,.........You may want to just play around with the parameters that are tunable, Ie, Tire pressures, castor, even camber ( with Adjustable ball joints ) wheel offset ( scrub radius ) toe setting. All these are things you can experiment with, hey, maybe you'll be the one that figures it out.
Who was the source for this answer?
 

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Sounds like two different things being described here. Bump steer and “death wobble”.

Bump steer is when you cycle the suspension and the steering wheel moves due to a difference in arc between the track bar and draglink. The steering wheel moves one way when the suspension cycles and moves right back to where you started after the suspension stops cycling. Typically not a violent shake back and forth. This can happen at any speed. Really obvious if you pop

Death wobble is when you hit a bump/crack in the road and the steering wheel shakes/rotates/cycles for a few seconds. This is due to funky harmonics in the front suspension and steering, which can be VERY violent.
 

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bump steer is when you are turning and hit a bump your vehicle jumps left/right
" Being able to measure bump steer is important because it is the phenomenon where the front wheels will change orientation (or steer themselves) without input from the steering wheel because of suspension movement. "

shimmy after a bump for 2 seconds or longer is death wobble or the onset thereof
fix: steering sector brace and hd trackbar
most steering sector brace kits also augment the trackbar brace on the frame.

you can try just the trackbar brace and HD trackbar, but the sector shaft brace improves the brace and also prevents the sector shaft from moving left/right so it's better than just the brace alone
 

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I am right with you. We must be measuring different locations.

Angle isn't the best due to the front bumper ski hanging down so far, but check out the attached picture. my Drag link & track bar are almost perfectly aligned.

Jeep Wrangler JL BUMP Steer 20210318_151650
That's not a great angle, you need to take it from the bottom front, so we can actually see the track bar's alignment without perspective coming into play.
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