If it's stock then it's either out of alignement or something is worn out. Make sure a quality shop does the alignment and the caster is set to stock spec.
Depending on mileage and how hard the previous owner was on the jeep, you may have a worn part. First things to check are the track bar and control arms (4). The track bar needs to be very tight, on both ends. The upper track bar mount should be very tight against the subframe. Probably have to remove the control arms (best done 1 at a time) to inspect the control arm bushings.
If all that checks out, it's on to the steering. The damper is a bandaid fix that can hide problems, the stock one sould be fine with stock size tires. Check for worn tierod ends, they're fairly inexpensive and should be replaced if you have high mileage.
Last I'd consider a heavier draglink and tierod. It's easy to flex the stock pieces by hand, and they flex when driving as well. This flex could lead to or aggravate this death wobble.
How many miles on this jeep?