tire imbalance can definitely trigger it.
everything that can move should be suspected and inspected. have someone violently saw the steering wheel back and forth from 10oclock to 2oclock while you watch and feel every joint up front. pay close attention to the aforementioned track bar bracket for any movement (plus check for cracks in teh side of the frame between the track bar bracket and steering box). look at the balljoints and bushings too. if your control arms are original, it might be time to replace them because the rubber just gives up over time (I prefer the WJ lower arms). jack up one tire at a time and violently shake it (side to side, not in the rotation direction) with your hands at 9oclock and 3oclock, and then with your hands at 6oclock and 12oclock. use a crowbar to try and pry up the ball joints from the knuckle. any movement is bad. 9/3 shows problems in the wheel bearings, 6/12 in the balljoints.
DW is a complicated thing that won't have a single source. it's a combination of small slop in things that leads to uncontrolled side to side oscillation of the tires that builds on itself with each lurch and thus tries to kill you. (comes with the territory of the suspension design). plus caster comes in to play with lifted Jeeps. fixing a single thing can sometimes bring it back under control juuuust enough to prevent the next event, but I always encourage replacing anything that is even remotely bad up front to get ahead of the problem.