4runner

I have a 99 jeep grand Cherokee Limited 4.7 V-8 that started the death wobble. I replaced all the front and rear control arms with new arms with new bushings in them. I also replaced the sway bars front and rear as well as all tie rod ends. Also put in a new steering stabilizer and then had a 4 wheel alignment done at Firestone. It drove smooth after that for about 2 months now. The other day I got a little shimmy int the front end today the death wobble was back for a moment. Does anybody know what else this could be cause I know the Cherokees are infamous for their death wobble.