Death wobble. Loose or damaged suspension/ steering components.
Had it happen on a Jeep ZJ w 135k on it. New steering stabilizer and it was gone. Would shake violently at 35 mph.
Came on all of a sudden.
Buddys kid lifted an XJ and had it. At about 50 mph. Told him they didn't tighten things up enough. Didnt believe me. finally they went through it and cranked em, and it went away.
Its also fun when a track bar comes loose/ off, eapecially on curves w traffic.
