Been a while sense I've been on. Recently my jeep (01XJ) has developed a terrible vibrations around 15, 25 and 35 mph. It goes away under hard throttle or if I'm off throttle completely. Did u joints and ball joints recently so it's not that. Feels like it's from the rear. Any suggestions? I can post a video later today.

 

Check your motor mounts and transmission mount and replace them all altogether.

Edit: Vibes are probably felt in the rear due to its being lighter and basically a hollow shell; the front has the motor to weigh it down.