Death Wobble

[Fshnfvr]

Just got death wobble for the first time in my 20 Plus years owning jeeps. Stock 87 Comanche 4X4. Checked all the steering components all are tight and I see no issues. Ball joints seem fine. Tires are older but I don’t see anything wrong with them. I have to get over 70 mph for it to happen. 
 

only recent change is I added a heavier front bumper. I planned to wait  till I lifted the Jeep to add it but I needed it out of the way.

 

With the new bumper the front end definitely sways and bounces more like the springs are worn. Any chance it’s the springs?  Shocks are a year old everything else is original. 

[MiNi Beast]

Check Track bar and mounting hole on axle mount. Side to side movement is bad 👎 check control bushings for excessive wear. Can always rotate tires to verify not a bad belt in tire. Also can check steering gear box mounting at frame rail, spacer plate behind box can break down and allow play there as well. And while there check track bar frame mount as well to ensure bolts are tight. Good luck. 👍

[phatton]

I have had this experience with my Comanche before and just recently had it happen a bout a week ago.  In my case it always seems to be a tire issue.  When I had the wobble last week, I rotated the tires (8000 miles on them).  The truck still wobbled.  I checked all the front suspension components and everything was tight and in spec.  I rebalanced the front tires had to remove a very small amount off weight from one and add a small amount to the other.  Road tested the rig and am problem free.  When I said a small amount of weight I'm talking about 3 ounces.  In addressing death wobble the first thing to check is tire wear and balance, next would be alignment, Then front suspension parts within spec.  Hope this helps.

[Eagle]

Tire balance.

 

[Pete M]

tire imbalance can definitely trigger it. 

 

everything that can move should be suspected and inspected.  have someone violently saw the steering wheel back and forth from 10oclock to 2oclock while you watch and feel every joint up front.  pay close attention to the aforementioned track bar bracket for any movement (plus check for cracks in teh side of the frame between the track bar bracket and steering box).  look at the balljoints and bushings too.  if your control arms are original, it might be time to replace them because the rubber just gives up over time (I prefer the WJ lower arms).  jack up one tire at a time and violently shake it (side to side, not in the rotation direction) with your hands at 9oclock and 3oclock, and then with your hands at 6oclock and 12oclock.  use a crowbar to try and pry up the ball joints from the knuckle.  any movement is bad.  9/3 shows problems in the wheel bearings, 6/12 in the balljoints. 

 

DW is a complicated thing that won't have a single source.  it's a combination of small slop in things that leads to uncontrolled side to side oscillation of the tires that builds on itself with each lurch and thus tries to kill you. (comes with the territory of the suspension design).  plus caster comes in to play with lifted Jeeps.  fixing a single thing can sometimes bring it back under control juuuust enough to prevent the next event, but I always encourage replacing anything that is even remotely bad up front to get ahead of the problem.  

 

 

[JMO413]

Road force tire balance will tell you exactly how good it bad your tires are. This would be my first step with anything speed related.

[omega_rugal]

if everything these fine people tells you doesnt work, make sure the steering box is tight and the bolts that hold it to the frame are not loose, that caused the death wobble in mine