Jeep JK steering shimmy

[Ryanc]

It appears that I get a shimmy/shake between 60-70mph, and it only happens when I am weighted down with cargo. Its also intermittant, it will happen for a mile or two, then stop for a while. Any thoughts?

 

[NuggetHoarder]

start cheap and work your way to more expensive....

• 
  [*]tire out of balance or tire delaminating or bent rim or bad alignment or flatspotting or tire pressure - check for missing balance weights, bent rims, and delaminating tires - switch tires front to back and see if it goes away
  [*]motor mounts - rev up engine to high RPM while sitting in driveway. Look at the motor for banging or clicking
  [*]struts - jack up and wiggle your tire - if you have a bad strut it will show itself
  [*]lifted components /suspension torqued too tight too soon - did you lift your truck or mess with suspension/transfer case/skid plates/etc? If so, you may need to loosen the bolts, drive around the block 10 times, bounce it off some curbs etc, and then tighten everything back up.
  [*]bent axle - if you've tried all the above, then you may be looking at a bent axle
  [*]bad and/or warped rotors - your symptoms don't point to this, but I put it in here in case you get this far down the list - if you get this far consider that it's your brake system
  

 

[Bennyhana]

Could be that when it's loaded down it puts the suspension at a certain geometry and when you his a certain part/type of road it just hits that frequency and the shimmy. But definetly try what nuggethoarder suggested.

 

[Number 7]

That sounds like loose ball joints. George:sombrero:

 

[jeep-N-montero]

Yes, loose ball joints can act like this when they are unweighted. Additionally, when the rear is loaded and brings the front up slightly, this will sightly change the front to rear tracking with the front wheels being sightly more to one side than the rears.

 

[Ryanc]

I dont think it is the balljoints, just replaced with dynatrac prosteers. I have checked every joint, appears to be working normally. All suspension components were tightened with vehicle on the ground and are checked frequently with a calibrated torque wrench to spec. My hunch is out of balance tires. These good year MTRs have been the bain of my existence with keeping them balanced. The fact that I initially did not think it was them was due to the shimmy/shake revealing itself while weighted down.

 

[jeep-N-montero]

I dont think it is the balljoints, just replaced with dynatrac prosteers. I have checked every joint, appears to be working normally. All suspension components were tightened with vehicle on the ground and are checked frequently with a calibrated torque wrench to spec. My hunch is out of balance tires. These good year MTRs have been the bain of my existence with keeping them balanced. The fact that I initially did not think it was them was due to the shimmy/shake revealing itself while weighted down.

My MT/R's are just fine at highway speeds even with some fresh chunks out of them 2 weeks ago.

 

[Uticon]

Check your shock mounts. Mine both front and back had oblong holes that i had to fix by welding washers on the axle mounts.

 

[Ryanc]

Check your shock mounts. Mine both front and back had oblong holes that i had to fix by welding washers on the axle mounts.

Did you have a similar issue?

 

[Uticon]

Yeah i had death wobble. We started with the shock mounts which were bad, then the track bar mounts which were bad but not as bad.
Then the steering stabilizer then ball joints.
The ball joints are what fixed it.

 

[wardrow]

It appears that I get a shimmy/shake between 60-70mph, and it only happens when I am weighted down with cargo. Its also intermittant, it will happen for a mile or two, then stop for a while. Any thoughts?

Re-lode your jeep up and get an alignment and Re-balance your tires of you have not done so recently.

 

[Ryanc]

Allright, I unloaded, dropped PSI down to 28, and the shakes happened. Running GY MTR 35x1250x17, load C, Max cold 35psi. The higher PSI, it appears less shimmy. Going to try and inch up the psi and see what happens.

 

[JPK]

Have you read about using Air Soft pellets to help balance the tires?

Shimmies can be out of balance tires, but death wobble is something worn or loose with the suspension or the steering. The most common cause, from what I've read, is loose track bar mounts or ovaled mounting holes. Then tie rod ends and adjustment bolts... You have new and top quality ball joints, so its not them...

On JKOwners.com there is a lenghty thread on finding and fixing DW, and while focused on the JK's, it really has universal application. It under "Moddified."

JPK