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2021 gladiator death wobble

seven30

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Those are straight axles - not live. They aren't front wheel drive. So the front axle is a dead axle.

They are a single I beam setup normally with leaf springs. They have king pins on each end. There is one tie rod that goes from left to right with the pitman connected to the left steering knuckle with a drag link directly to the left knuckle. Very very different situation. The front axle doesn't articulate the same at all. You can't compare them.
As the axle moves up and down- as little as they do - the pitman on the steering gear is straight down from the gear in most cases so that the end of the pitman is almost a direct line back to the steering knuckle.
There's not much "swinging in an arc" to a semi suspension as there is any live solid axle vehicle. Very different steering, very different angles, almost nothing swings in much of an arc, the pitman is almost straight across from the knuckle so the drag link is almost parallel to the ground.
Everyone is forgetting the arcs things move in on a pickup like the large Ford or many Jeeps without IFS. Semis have much straighter steering and suspension movement.
Not that it can't happen - but if you've worked on them (I have worked on the steering parts) or maybe even seen the inspections they must go through..... it's no wonder you haven't seen one do that. (plus the fact it's very very different in geometry!)
Point taken on the single piece tierod. Much stiffer.

I was attempting to make the point that a beam axle, unlike IFS, is quite susceptible to shimmy/DW and a joint which performs adequately in an IFS environment may prove deficient in a beam axle setup.

Mechanics trained on IFS may not flag a joint unless its got perceptible play. That simply may not be good enough in a beam axle environment.

The joint has to resist being deflected to a considerably greater degree than it would in an IFS setup.
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Mechanics trained on IFS may not flag a joint unless its got perceptible play. That simply may not be good enough in a beam axle environment.
IF that's the case they were not "Trained". I went to college and then later short factory training sessions. Even in my college books it shows and explains the correct, proper methods for checking ball joints.
I have run into well-trained mechanics, and then those who think they are mechanics and believe they know what they are doing because cousin Bubba or a neighbor taught them.

Then there's the trouble with warranty work - they get paid for fixing the issues under warranty, not time for diagnosis, and barely get reimbursed for the repair itself.
In many cases, diagnosing a problem can take real time - if it's warranty, they lose. If it's billable, they'll charge for that time.

Like I said - Eagles are IFS and they have a stabilizer............

With our Jeeps, it's often the angles that things operate under, and the flexing of parts like the track bar and drag link and so on. They operate under angles that mean the pressure isn't directly end-to-end. There's complex geometry and forces going on that aren't present in other systems. In the case of semi tractors, it's pretty much always worn parts.
Jeeps need to be looked at not by comparison to other designs or systems, but independently and not necessarily compared.
Track bar - operates at an angle. Drag link - at an angle. Any changes change the design geometry. Any wear or things not torqued will come into play.
 

seven30

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IF that's the case they were not "Trained". I went to college and then later short factory training sessions. Even in my college books it shows and explains the correct, proper methods for checking ball joints.
I have run into well-trained mechanics, and then those who think they are mechanics and believe they know what they are doing because cousin Bubba or a neighbor taught them.

Then there's the trouble with warranty work - they get paid for fixing the issues under warranty, not time for diagnosis, and barely get reimbursed for the repair itself.
In many cases, diagnosing a problem can take real time - if it's warranty, they lose. If it's billable, they'll charge for that time.

Like I said - Eagles are IFS and they have a stabilizer............

With our Jeeps, it's often the angles that things operate under, and the flexing of parts like the track bar and drag link and so on. They operate under angles that mean the pressure isn't directly end-to-end. There's complex geometry and forces going on that aren't present in other systems. In the case of semi tractors, it's pretty much always worn parts.
Jeeps need to be looked at not by comparison to other designs or systems, but independently and not necessarily compared.
Track bar - operates at an angle. Drag link - at an angle. Any changes change the design geometry. Any wear or things not torqued will come into play.

So as predicted, the dealer said its stabilizer and its backordered.

Sad.

So sad.
 

seven30

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Since the dealer is unable to get the stock stabilizer Im installing one of these: Fox Shox PS Stabilizer IFP 98524173

The -14 weather I was in a couple of weeks ago may be the reason the stock is leaking.
 

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@14634 miles experienced a front wobble again on what seems to be the left side again.

4th time, not as cold 47 degrees. In the 2-3 seconds while on the patch, I experienced a left to right vibration in the steering wheel. It was also a pronounced wobble on the left side as well. This continued after the lane patch was needed and the surface was smooth and normal. I slowed down to 55, and the wobble stopped and steering wheel vibration stopped as well. This is the same place it has happened before. Now that I can repeat this in the same spot I will do some investigation on the front suspension. Here is what I did when I got home today to check front suspension components.

My daughter got into the driver’s seat and turned the steering right to left with the engine off and did not feel or see any movement or slop in the suspension components including the steering box.

Now with the engine running, and turning the steering right to left, I felt some slop in the drag link, (more of a clunk) did not see or feel slop in the steering box or any other components move during this time. I have an appointment with Jeep on Wednesday, interested to see if they find the same thing. I will update what they say they have found.

My plan if the dealer does not find anything is as follows.
Go through and re-torque all the front suspension parts
Check both wheels for any movement in the ball joints, or the wheel bearing (or hub)
Go to a credible alignment shop and check the alignment once the previous 2 steps are done.

This jeep just makes me smile, I am saddened that @ 14K miles I am now chasing something that should not be occurring.
 

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@14634 miles experienced a front wobble again on what seems to be the left side again.

4th time, not as cold 47 degrees. In the 2-3 seconds while on the patch, I experienced a left to right vibration in the steering wheel. It was also a pronounced wobble on the left side as well. This continued after the lane patch was needed and the surface was smooth and normal. I slowed down to 55, and the wobble stopped and steering wheel vibration stopped as well. This is the same place it has happened before. Now that I can repeat this in the same spot I will do some investigation on the front suspension. Here is what I did when I got home today to check front suspension components.

My daughter got into the driver’s seat and turned the steering right to left with the engine off and did not feel or see any movement or slop in the suspension components including the steering box.

Now with the engine running, and turning the steering right to left, I felt some slop in the drag link, (more of a clunk) did not see or feel slop in the steering box or any other components move during this time. I have an appointment with Jeep on Wednesday, interested to see if they find the same thing. I will update what they say they have found.

My plan if the dealer does not find anything is as follows.
Go through and re-torque all the front suspension parts
Check both wheels for any movement in the ball joints, or the wheel bearing (or hub)
Go to a credible alignment shop and check the alignment once the previous 2 steps are done.

This jeep just makes me smile, I am saddened that @ 14K miles I am now chasing something that should not be occurring.
Why wait for the dealership? If you think you’ve found a clunk go ahead and retorque it. If it goes away you’ve solved the problem and don’t have to wait for the dealership shenanigans.
 

piroman683

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Check your thirst angle. If the rear and front axles are not centered with each other you can get DW
 

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Check your thirst angle. If the rear and front axles are not centered with each other you can get DW
That's not quite the definition of thrust angle. It's more concerned with the drive axle being centered and a line perpendicular to the rear or drive axle runs straight up the center of the vehicle and that the rear wheels are parallel to that line

The thrust angle is an imaginary line drawn perpendicular to the rear axle’s centerline.
It compares the direction that the rear axle is aimed with the centerline of the vehicle. It also confirms if the rear axle is parallel to its front axle.

Thrust is more concerned with the individual "toe" of the rear wheels and that the rear or drive axle is perfectly perpendicular with the center of the vehicle.

That's why rear "toe" is checked and the rear axle checked for "Square" with the vehicle.

It usually causes a pull, or the steering wheel being off-centered when driving but ok with the front wheel toe being centered.

(One definition from a book - A thrust condition exists when the rear individual toe is not equal.)


Jeep Gladiator 2021 gladiator death wobble 1644727287864


Jeep Gladiator 2021 gladiator death wobble 1644727338696
 

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I haven't read every reply so forgive me if this has been covered. After herding CJs (yes you do herd them. Not steer them) for almost 50 years I can empathize with your frustration. My 2020 started showing early signs of DW, in to the dealer to be checked out and they found a failed steering damper, that's NOT the fix but I put a new one on. A fox. The dealer tech said they like to align the new jeeps with a little more toe in to help with shakes esp with big tires. Talking wit h a friend who's had issues with his 21 Mojave already and he was adamant that more caster was the real answer. My mj experience would support that theory. He went on to say get an adjustable UPPER control arm set to add the caster so that the housing wasn't extended out into the steering linkage space. So far the dampened has addressed mine but I plan to add a smidgen of toe in and look for some adjustable control arms, after I talk to the alignment guy I've been using.
 

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Holy crap, Batman.

So much wrong in this thread. People, listen to @ShadowsPapa.

In short, a lot of what's being called "death wobble" isn't - sorry. Unless you have to bring your Jeep to a complete (or darn near complete) stop, it ain't death wobble.

Also, WTF did you think would happen by monkeying with the suspension? Speaking from experience here. I get it, a lifted Jeep on big tires looks nice, it also feels like something you want offroad. But you know what it ain't? It ain't something you want on-road.

Spacer lifts. Lift kits without adjustable control arms. Lifts without adjustable trackbars, etc., etc., etc., This is the cost saving crap that gets people into these situations. Either don't lift it, or spend the cash.

Also, as has been said, torque things to their proper (as documented by Jeep) specs. Use a torque wrench - don't just guess. Check for worn out bolt holes, and loose and damaged parts. Shit gets worn out when it's ran out of spec.

IMHO, been there, done that (on both lifting and death wobble). I'm happy staying stock.
 

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piroman683

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That's not quite the definition of thrust angle. It's more concerned with the drive axle being centered and a line perpendicular to the rear or drive axle runs straight up the center of the vehicle and that the rear wheels are parallel to that line

The thrust angle is an imaginary line drawn perpendicular to the rear axle’s centerline.
It compares the direction that the rear axle is aimed with the centerline of the vehicle. It also confirms if the rear axle is parallel to its front axle.

Thrust is more concerned with the individual "toe" of the rear wheels and that the rear or drive axle is perfectly perpendicular with the center of the vehicle.

That's why rear "toe" is checked and the rear axle checked for "Square" with the vehicle.

It usually causes a pull, or the steering wheel being off-centered when driving but ok with the front wheel toe being centered.

(One definition from a book - A thrust condition exists when the rear individual toe is not equal.)


1644727287864.png


1644727338696.png
Far better than what I wrote. I only brought up 2 different points without clearly delineating between the two.

I definitely think alignments are important here because adjustable control arms can be off by an 1/8 on an inch and that could put you just out of tolerance for thrust angle. This happened to me after I did a lift on mine, turns out I miss measured a lower front control arm and was 3/16 too long. I found this out because on a specific bump on my road I'd get the wobble. Once I corrected the length problem went away.

Another time when I swapped to an adjustable front track bar I made it a bit too long so the front axle was shifted to the right vs being centered with the rear. Again, fixed that an problem went away.

So those experiencing DW definitely check your geometry,(alignment, control arm lengths), check torque, and don't be in a rush to check everything.

I beat the crap out of my truck and have zero DW issues. I actually just sheared a sway bar link in Landers 2 weeks ago do about 55mph through some smaller whoops. Still no DW.
 

seven30

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A few months ago I saw a JT coming my way in the opposite lane. The drivers wheel looked like it was trying to rip itself of the axle. Frightening. The driver never even slowed. The forces were clearly high. I can't imagine a spring loaded ball joint being able to resist them at that point.
 

seven30

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So after a couple of days with the fox IFP damper no DW. I can detect occasional steering shake that feels like it would break into DW if not for damper action. Steering is otherwise about the same. Perhaps a bit less tendency to wander.

For point of reference I compare to our beam axle 2000 4wd GC with 110K and original shocks/damper. Its uncanny how well it steers no matter the surface. No wander, no shimmy no steering box issues.

Of course I would not drive the GC as hard as the JT either. The JT can take some punishment without complaint.
 

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So after a couple of days with the fox IFP damper no DW. I can detect occasional steering shake that feels like it would break into DW if not for damper action. Steering is otherwise about the same. Perhaps a bit less tendency to wander.

For point of reference I compare to our beam axle 2000 4wd GC with 110K and original shocks/damper. Its uncanny how well it steers no matter the surface. No wander, no shimmy no steering box issues.

Of course I would not drive the GC as hard as the JT either. The JT can take some punishment without complaint.
Sounds like the new damper is hiding it well, but the cause of the problem is still there on the back end. I’d definitely want to find the source.
 

seven30

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Yep I agree. Sadly I'm on my own as there is no way the dealer will investigate this further once they install a new stock damper.
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