Truck: 2006 rcsb
Problem: vibration while driving at low speed 30-40 and hogh speed past 70
Solutions: First time was simple, the bolts to the rear u joint and differential backed out. Second time driveshaft blew in half my fault for stayin stock and goin over 120 on the highway, bought a new stronger ds all new u joints and after 6 months vibration came back. Thought i had to replace rear u joint due to play in bearing caps but not so, i used the old bolts from when i blew the old one in half so went up to orielys and bought some new bolts and clamps only $6. Installed and viration is gone and no play in the joint Heres some pix....

 

How did the head of those bolts get so messed up? Is that where the vibration came from? throwing it out of balance?

 

They got chewed up when the shaft blew and the back half was floppin around. I assume it messed up the little u clamps as well gaping them so it wasnt holdin the u joint tight enough into the rear yoke