drive shaft woes

[alderan33]

I need help with this one guys. It's a strange one. So I am restoring my 72 C10 and I have the bed off and have been working on the frame, front end, etc.. I have the motor out and decided to replace the u joints. No problems with them. I began reinstalling the rear section of the drive shaft (2 piece) and after securing the u joint to the rear end I attempted to bolt up the carrier bearing. And it is 1 1/2" too short to line up with the mount on the truck. I did nothing with the carrier bearing. I am stumped at why and how this could happen. The truck is a long bed. The only thing I can think of is the absence of all the extra weight from the bed makes it sit differently? I could really use some advice and I would be most appreciative of any help. Thanks!

[PanhandleShantyman]

I had the same "WTH?" moment last month when I reinstalled the 2-piece drive shaft of my '69 after dropping it for the first time to replace the clutch. It was "short" at the back just as you describe, after I connected the front end of the drive shaft back to the tranny and bolted up the center support bearing bracket. But, I realized the rear section of the drive shaft can slide in and out from the back end of the center support bearing, and that had to be where I needed to make the appropriate adjustment. I guess the process of backing the drive shaft out of the differential had made it slide in at that connection point. So I just whacked the drive shaft backwards right behind the center support bearing a few times with my trusty BFH to slide it backwards until the U joint slid back enough, and hooked it back up, no further issue.

[alderan33]

Originally Posted by PanhandleShantyman

I had the same "WTH?" moment last month when I reinstalled the 2-piece drive shaft of my '69 after dropping it for the first time to replace the clutch. It was "short" at the back just as you describe, after I connected the front end of the drive shaft back to the tranny and bolted up the center support bearing bracket. But, I realized the rear section of the drive shaft can slide in and out from the back end of the center support bearing, and that had to be where I needed to make the appropriate adjustment. I guess the process of backing the drive shaft out of the differential had made it slide in at that connection point. So I just whacked the drive shaft backwards right behind the center support bearing a few times with my trusty BFH to slide it backwards until the U joint slid back enough, and hooked it back up, no further issue.

Much appreciated. I will give this a try. I actually had installed the rear of the drive shaft first. I will reverse the procedure and find a BFH to remedy the problem. Thanks again!

[Rust_never_sleeps]

Did you try flipping it the other way? ;-)

[alderan33]

Yeah I still can't figure this out. I have beat on this driveshaft but it's not budging. Any other ideas?

[Willshook]

If the mount for the carrier bearing is fore/aft, there's about 1" of adjustment slots there.

[3drburb]

Try installing the carrier bearing with the driveshaft to the cross member first, then to the rear end.

[sixty8HDC30]

am I understanding that the splined slip joint is stuck in the compressed position? if thats the case then filling it with grease at the grease point should force it to extend.