Track Bar Play / Death Wobble (1 Viewer)

[motormayhem]

I've been trying to track down a case of death wobble for a month or two now. The truck drives well on the highway + around town. However, if I hit a moderately large pot hole between ~35-40mph the steering will start to shimmy and left unchecked it will get uncontrollable until I slow down. If I jerk the steering or change speed I can usually get it to stop before it takes over. I have checked the steering a few times now and everything seems tight. I aired the tires down to 10PSI to load the steering while turning and the drag link/tie rod ends have no perceptible play. I also checked the trunnion bearings by jacking the truck up and using a pry bar to move the wheel up and down - no perceptible play. Wheel bearings are also tight. When I was checking the steering by having my wife turn the wheels left / right I noticed the bushings in the track bar were flexing left right. The upper ~1/8in and the lower ~1/16in. These are OEM bushings that are probably 3 years old and have ~30K of road/off road on them. Is that too much play? I'm surprised they would be worn being relatively new / on a vehicle that isn't a daily driver. Any other suggestions to check? It didn't do this previously, so its something that has developed over the last year or so with not changes to tires/suspension.

 

[OffRoadScott]

If you haven't done so yet I would check the studs/nuts on the bottom of the knuckles. I know you mentioned the steering components seemed tight but I would just check the knuckle studs.

 

[motormayhem]

If you haven't done so yet I would check the studs/nuts on the bottom of the knuckles. I know you mentioned the steering components seemed tight but I would just check the knuckle studs.

Yup, checked those a few times over the years. They were all tight. Earlier today while checking the steering I did notice the front inner area on the pass side had a little “crack” in the grease at the joint between the knuckle and arm like the joint had flexed a little, but the flexing “crack” was local to that corner and not across the rest of the knuckle/arm joint. Just in case, I pulled all the nuts off, cleaned the threads and such, and re-installed/locktite/torqued everything. As expected it didn’t make a change to the death wobble.

 

[ozarkmud]

What sized tires are you running? What does your caster look like with them?

 

[motormayhem]

255/85/R16 tires
Caster is 3deg when I had it checked after lifting it and installing caster plates.

 

[leonard_nemoy]

Check your frame for cracks where the gear box mounts and where the panhard attaches to the frame. This is a known issue.

Also put a wrench on your panhard and control arm hardware and make sure it is torqued.

Goodluck

 

[motormayhem]

I checked the radius arms and panhard bolts and they were tight.

A few months back when I started chasing this down I found some hairline cracks around the panhard and welded them up. They were pretty small so I don’t think there was a lot of movement from them yet, but braced and welded it up.

I did notice the panhard bushings had some play (see my first post). They are not that old so not sure if that’s normal or not.

Panhard / Frame Crack Repair Questions

I've noticed my truck has a small crack where the panhard bracket welds to the frame under the steering box. From researching, it seems this is a relatively common location for cracking. I need to do a bit more cleaning / inspection, but it seems to be isolated to just the weld / panhard bracket...

forum.ih8mud.com

 

[leonard_nemoy]

I checked the radius arms and panhard bolts and they were tight.

A few months back when I started chasing this down I found some hairline cracks around the panhard and welded them up. They were pretty small so I don’t think there was a lot of movement from them yet, but braced and welded it up.

I did notice the panhard bushings had some play (see my first post). They are not that old so not sure if that’s normal or not.

Panhard / Frame Crack Repair Questions

I've noticed my truck has a small crack where the panhard bracket welds to the frame under the steering box. From researching, it seems this is a relatively common location for cracking. I need to do a bit more cleaning / inspection, but it seems to be isolated to just the weld / panhard bracket...

forum.ih8mud.com

Rubber bushings will flex, saying how much flex is normal is a tough call.

If you really want to determine if the bushings are bad than I would recommend pulling the panhard. Mounting it in a vise. Than take a pipe or something and stick it in the bushing. Than pry the bushing and give it a close inspection while it flexes. If you see tears or cracks than they are shot.

 

[Rusty Marlin]

the panhard bar is very easy to pull out and look at the bushings.
Mine looked like this: Death Wobble?!--Check your bushings. - https://forum.ih8mud.com/threads/death-wobble-check-your-bushings.1229514/ and this was the cause of my death wobble.