steering shudder/death wobble

[tugalo]

1988 2WD, longbed, B/A10 tranny.  Have a steering wheel shudder/vibration commencing between 45 and 50 MPh and remaining constant as i speed up.  if i dropped the left front wheel in a hole at speed, she would go into death wobble and almost change lanes.  Found several cracks in the frame around the steering box.  Got the frame welded, installed the heavy duty aftermarket steering box brace, Xj steering box, and new upper and lower control arms.  Replaced all wheel bearings.  Took her today for a 4 wheel balance/rotation and alignment.  The steering wheel vibration has changed, but it is still evident at the same speeds.  If i'm going down-hill and push in the clutch to unload the torque, she still has the vibration, so i'm assuming the problem is still in the running gear and not motor mounts

Any ideas what to check next from the front end experts?

[oleskool]

How are your ball joints? Did you replace track bar bushings when you did the control arms?  The easiest thing to do is have a friend turn the wheel left to right slowly and watch each connection point in the axle and frame to make sure you do not see movement. Also jack up each sides ball joints for excessive play. 

[tugalo]

i did not replace trackbar bushings.  I asked the alignment place to check for looseness but they didn't see anything wrong.  i was thinking maybe u joints but maybe track bar bushings would be more likely...........

[MiNi Beast]

I'm leaning towards a throw out bearing or worn clutch components. Even more so the pilot bearing.  seems like you have the front button up other then swap out tires perhaps..

[MiNi Beast]

Double check trans mount with pry bar. 

[oleskool]

If you still have death wobble it’s not related to i joints etc. the vibrations definitely could be for sure. Tire vibration stays when you let off the gas. Typically drivetrain vibrations stay when you let of the gas etc. 

[rokinn]

Check your ball joints, particularly the lower non greasable ones for any noticeable rust that might be coming from inside.  If there is chances are they are bad.  

[tugalo]

Thanks for the replies.  the tranny mounts are a possibility, but if the vibration remains when i unload the torque, i think the vibrations would cease if it were the mounts.  Since the truck has over 300K, i think i will replace the track bar and the ball joints.  Any and all advice welcome.

[rokinn]

14 hours ago, tugalo said:

Thanks for the replies.  the tranny mounts are a possibility, but if the vibration remains when i unload the torque, i think the vibrations would cease if it were the mounts.  Since the truck has over 300K, i think i will replace the track bar and the ball joints.  Any and all advice welcome.

Make sure the track bar mounting holes aren't wallowed out.  The one on the axle side can have a proper size grade 8 welded on to the front for the easiest fix to that problem.  There is a kit you can buy, might want to do a search on CC to find out which it is.

 

I was able to get the proper adapter in the kit from Autozone.  Make sure you have a herfy breaker bar and a pipe to extend it for leverage.  Couldn't have done mine without it.  You may have to adjust axle and body relationship up or down to get best angle on breaking things loose.  Hope it's a warm space you are doing this in.  Good luck.

 

Just happened to have a link to the kit that's been recommended here.

 

https://kevinsoffroad.com/products/kor-9906-hw-track-bar-upgraded-hardware-kit