I have a new XJ i just recently bought. So it has a 3" Rough Country lift ,General Grabber at's. I have a very loud vibration coming from middle of the vehicle to the back. Thought it was a bad pinon angle so I had my buddy help me check it and we at to put some shims in it. Still loud so I pulled the drive shafts sent them to drive line service had new u-joints installed and re balanced still very loud. Thought it could be the rear end. Replaced the hole unit new carrier, gears and all new bearings still same old noise and vibration. It is very loud on acceleration at about 50 and up as soon as I let off the gas it gets quieter. Could this be a worn out transfer case?

Now the cruise control it worked a while back then quit and so did the gauge cluster. Had to put a new cluster in. But now My airbag light is on and my horn doesn't work and the cruise control indicator will not even light up. Also my dome lights wont turn on when I twist the headlight switch but they will turn on when I open a door. Could I have a bad clock spring? Bad wires? the fuses are all good. I did have to replace the brake lamp switch a few months ago. Any ideas or suggestions?

 

That's the "non-functional clockspring" trifecta right there. Notes on how to replace here:
https://www.cherokeeforum.com/f2/hor...working-57845/

Vibration...seems as though you've already changed everything south of the Transfer case. That'd be my next suspect.