We really should have a sticky topic on Death Wobble. There are people here that hate repeating themselves.
The diagnosis:
With the rig on the ground, have a buddy saw the steering wheel from 9 to 3, at a decent speed.
Lay in front of the rig, and start inspecting:
Upper and lower ball joints, both sides.
Steering linkage - tie rod ends, heims, etc. On drag link both sides, tie rod both sides.
Trac-bar (Panhard bar), axle bushing and frame ball-joint/tie-rod.
Since you're down there, if you have your brakes dust-shield removed, see if you can see the unit-bearing or hub move.
Since your down there, take a look at the control arm bushings, axle side and frame side. Not a likely culprit, but it has happened. And see if the control arms are straight.
You're looking for play between two steel parts on either side of the bushing/heim/tie-rod-end/ball-joint.
1/16th of an inch or less is ok, more is bad.
Balance the tires. If your rubber is oversized from stock, stick to static balance (rim weights) for a highway rig. Yes they look like sh!t on bling rims, but they work so much better than bb's/buckshot/pellets (dynamic balance) rolling around inside the tire. It's worked, until a part starts to wear out, then you'll get DW. Some swear by static, some by dynamic. *shrug* This is like arguing about 9mm vs .45
If you have big-arse bias ply tires, what are you doing on pavement anyways??
Wheel alignment. If running oversized, find a shop that can do better than 80% on their equipment with oversized tires.
Jack one side of the axle up, axle stand it, try to leave about an inch between the bottom of the tire and the ground - use a pry-bar to heave the wheel up, any noticeable movement or clicking sound is a bad unit-bearing or hub, and a ball-joint if you noticed it moving earlier.
Do Not Mask The Problem With Another Steering Stabilizer! Bump-steer is normal, especially with bigger tires and wheels. A properly engineered crossover steering setup is very expensive to build, thus automobile manufacturers cheap out because of the economies of scale. A steering stabilizer is technically not needed on the perfect setup. Those rigs with 2 or more steering stabs are masking big problems, stemming from a POS lift with POS engineering and POS design.
DW is a nasty beast to track down, don't feel bad that after some parts changes you only have a minor improvement. We are talking about 12+ mechanical joints that are designed to have deviances in thousandths of an inch, at stock. Add bigger and heavier tires and wheels. That turns into fractions of an inch, which turns into shimmey and eventually DW and broken parts.
All the replaceable parts in the front end are consumable. So when you're going to replace them, go bigger/better/badder than stock. I always replace with the next level or two up of balljoint, without going into the "adjustable" ones. Same with unit bearings. Same with tie-rod ends, or invest into a steering setup that uses rebuildable heim joints. Same with the trac-bar. The axle side bushing is notorious for moving the bolt around, and ovalling the bolt hole. Step up to the same outer-diameter bushing, with the next size up inner-diameter. Drill the hole to match, bolt up and torque. Put a tack weld or two on the bolt head to the bracket.
That, in a nutshell, is the cause, and potential fixes for DW. There is no silver bullet, magic cure, easy fix. It can be fixed on the first try, or the fortieth.
All this is doable in your garage, with some pals, on a saturday. It's not rocket science.
Don't give up, it's fixable.
Topic: Looking for jeep mechanic to address my Death Wobble at 70-80km/hr (Read 3902 times)