the death wobble is mostly caused by loose or bent front end parts....tie rod, ball joints, drag link, bent coil spring, tires out of balance, alignment issues.....
The most common cause on a JK...and probably the TJ is the front track bar is either loose, or one of the two bolts that holds the track bar in place is loose / or the bolt hole is wollowed out from a loose bolt vibrating in it.
I would have an alignment done, tires balanced by a good shop, and make sure to check every bolt in the front end for tightness.
I would so a search on any jeep site for the death wobble and you will find hundreds of answers, but these are the most common.
The steering stabilizer is just a mask for the problem, and will not be the end all fix.
