[sector95]

Do you have a single or 2-peice drive shaft?

Short bed=1 peice

Long bed/Extnd'd Cab=2 peice

Agree with potential U-joint failures.....Probably have them all replaced and replace them with greaseable joints. The 1 peice drive shaft has only 2 joints; the 2 peice has 3 or 4 plus a center bearing support which can go bad also....

The 1 peice drive shaft also has a requirement to periodically grease the front slip yoke where it engages the tail shaft of the transmission....an often neglected service.

Good luck

Mike
98Sierra