Death wobble is related to a loose track arm, either the bushing at the frame bracket or the ball joint on the axle. The bushing has to be torqued to 410 Ft. Lbs.
I dealt with this and fixed (Blamed) everything until I replaced the poly bushing with a heim and torqued it to 400+.
Before I got the 500lb tq wrench and did it right I could tell and feel when it was getting loose, one bump on the highway each day let me know.
Good luck, but that's where i'd start.
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