I searched but my problem is specific an really starting get on my nerves. Ok heres the deal I just put a dana 44 in the back of my 98 with new 4.56 gears a lock rite, new diff bearings, and wheel bearings. I also just rebuilt the transfer-case with all new bearings and a tera sye. also brand new rear drive shaft. i don't feel play in either yoke or in the slip yoke of the drive shaft. i currenlty don't have a front drive shaft so thats no the problem. Vibes start and get real bad right at about 75mph and seem to get better if i go up over 85. i'm at 6in of lift and shimed so the pinion angle is also good. vibe sounds real fast so its not a tire/wheel. Any sugestions. cause i'm lost and sorry for the long post just need help before i get mad and do something stupid, like sell the heep.