I put a 3 inch lift on my cherokee about 6 months ago. Within the last week it has now developed what I believe to be the "death wobble", 50 MPH seems to be the sweet spot where it wants to shake uncontrolably.  I was running 31 TSL's I have taken them off and put the stockers back on and that didn't help. I had already ordered a Rusty's steering stabilizer and that in combination with the stock unit still attached has slowed the problem down but it is still there. The trac bar has some vertical no horizontal play on the frame end could this be the problem or should it be doing that, the rest of the front end seems tight thanks for any help  

check all your ball joints, track bar ends, tie rod and steering link ends, and  your wheel bearings before ya buy anything, also the tire pressure.

the new stabilizer may help, it won't fix it.

it may only need a caster adjustment from the local allignment shop. when ya lift, it puts thigs out of wack if the aren't in the proper adjustment range..

here's a link so I don't have to rewrite the book!

http://www.mn-jeep.com/forum/showthread.php?t=8022