hey buddy
i just had that problem its ur u joints in drive shaft there is a place in charlotte nc called universal driveshaft they are cheap but do great work , does it shake at 25-35 mph, 60-75 bad if so its this

 

fix the track bar also

 

I can't get it safely above about 30-40. My u-joints have been replaced recently and still look to be good. I am going to replace the track bar bushings and try and tighten the tie rod end. I think the PO didnlt tighten it as tight as he should have. If that doesn't work I will replace both tie rod ends.

 

if its a bushing in the front end somewhere then its like this: when the bushing breaks off or deteriorates, its like leaving a bolt half way in and not tightening it. it feels like the piece that needs to be secured is so loose that its ready to fall off.

if its a u joint or a counter weight on the drive shaft, its easy to replace and inexpensive. a bushing might be expensive due to labor reasons and fighting against rust.

it could be something as simple as mud in the back side of your rims that is dried on.

 

Im having a very similar problem. My question is could the frame being cracked right below the steering box cause this death wobble

 

If the whole steering box is moving, I think it could cause the wobble. Try watching the steering box and have someone wiggle the steering wheel back and forth to see if it moves. Also check the bushings mentioned above. My 78 had this issue and it turned out to be the Trac bar bushing was completely gone on one side. Go that fixed and some new tires and it was fine.

 

Death Wobble

 

Holy crap! Now imagine that but on my bronco and with 35 inch tires...

 

Been there and its no fun. some thing is worn or loose on front end. Check all that then upgrade steering stabilizer for piece of mind. keep em aired down a bit until you fix

 

Get in, sit down, hold on, and shut up.