My 93 2wd has a vibration past 55. I have found the problem and it seems to be my driveshaft. The yolk as it enters the transmission is leaking AND there is a lot of play in the front U-joints. When I pulled on the driveshaft I could see the yoke moving in the housing. Jeep specialist wants $289 to "rebuild". He said I couldn't do it myself. It would be really nice (cheap) to prove him wrong. Need your help for this.