i have a 96 grand cherokee Orvis 5.2L and have been chasing this problem for over a week. i have replaced the steering stabilizer, track bar, drag links , inner and outer tie rods, upper and lower ball joints, sway bar links, and lower control arms, new wheel bearings on both sides, along with alignment and balanced and rotated the tires. im short of replacing the pitman arm and the upper control arm bushings but they seem to be in good shape. the problem i have now is at 50mph it use to be around 40mph but after replacing the lower control arms last night it only does it now at 50mph. i dont know what else to do to solve this as it is my daily driver and i love my jeep. is it true when replacing the lower control arms you dont want to tighten the bolts all the way down until you let the weight set on the axle to get ride height correct. because i tightened them down before i set the vehicle back down and i am wondering if that may still cause the shake im experiencing at 50mph. please help as im new to jeeps and trying to do this asap. thank you.

 

This is from my '93 GC manual..

UPPER SUSPENSION ARM
INSTALLATION (1) Position the upper suspension arm at the axle and frame rail. (2) Install the bolts and finger tighten the nuts. (3) Remove the supports and lower the vehicle. (4) Tighten the nut at the axle and frame bracket to 75 NIm (55 ft. lbs.) torque.
You might also check the wheel bearings, and have another look at those upper control arm bushings. Good luck!

 

thank you and yes i forgot to mention that have replaced both sides of wheel bearings on it. i will try that and set the torque while vehicle is lowered on weight as well as look at the upper control arm bushings. thank you

 

Are you lifted and have you got aftermarket steering components?

 

its an Orvis edition and i think i came lifted some. its nothing major by any means because everything looks close to stock. maybe a couple of inches, no more than 3 at the very most. no aftermarket parts on any suspension. have bought all parts by the vin# and everything has matched up. im planning on doing the front upper control arms and bushings this evening. and take it back in for an alignment and just hope and pray this solves the issue. the last parts i can think to replace is the pitman arm and maybe the shocks heck idk.

 

Have you looked under it while someone else saws the steering wheel back and forth? Any loose joints will be apparent

 

Check the steering box for looseness either in the mounting or the gear lash. Sometimes just 1/8 of a turn on the adjustment screw makes a big difference.