Backround: We have a 96 GC with 91,000 miles. About ten times since November the Jeep will shake violently at speeds over 45 mph. It doesn't always happen at the same speed though. Slowing to under 20mph will stop the shakes. In anticipation of our 250 mile vacation trip I rotated and balanced the tires, and replaced all 4 shocks (Rancho 5000's). I couldn't move any suspension parts with a crowbar except the ball joints have just enough up and down movement to to say that there is movement can be felt but not seen. No sideways movement. The first drive after the work I had the shakes again after only 1 1/2 miles. It lasted 3 miles (I only slowed to about 35~40 mph) until I had a stop sign. With only 4 days before vacation I dropped the front driveshaft. Unsure that it made a difference, but made the trip without driveshaft or the shakes. All the driveshaft universals feel good. The front-most one is only 1 yr old.
When a bump is hit Jeep kinda feels like we get an extra shudder after the suspension movement. Not like bad shocks though. It may even be how the shakes actually start but they are so seldom that it catches you by suprise.
My next step was going to be a new steering stabilizer but the shake is not in the steering wheel.
Today, with the wife driving and myself underneath, I noticed the front axle rotating (caster) while shifting from drive to reverse and back and playing with the brakes. The movement is in the bushing at the front of the lower suspension bars where the caster adjusters are located. Just by eye it seems to be about 1/8th inch of movement. I could not move this with the crowbar two week ago. I imagine that this should definately be affecting the caster. It seems that it could also cause the "extra shudder" but how about the shakes? Are these bushings able to be replaced? Do I need whole new arms? Can this be done without an air compressor and/or a torch? Just basic hand tools in a driveway.
Any comments or other ideas are greatly appreciated.
Thanks. Jim