1959 drive train vibration

[kkarrer]

Ok guys, I know I've seen this problem and solution posted before, but a search didn't turn up an answer.  I have a drive train vibration in my 59 convertible.  It happens at the top of each shift point and then at about 60 mph.  I'm pretty sure that it's an angle issue (drive shaft, engine, rear end) as the carrier bearing seems ok and I have no reason to suspect the drive shaft.  I've seen this happen when cars are restored (engine out, trans out , and new pads installed).  A big issue is that the drive shaft is not really exposed, but I think that I can get a digital readout level on it as mine is magnetized.  I would think that you could shim the trans mounts or the diff. or both, but I'd like to know if anyone has the approximate angle setting as I'm anticipating a lot of trial and error on this as it is.
As always, any help would be appreciated.
Thanks,
Ken Karrer
CenTex Reg. Dir.
1959 convertible

[Bobby B]

Ken,
Hi. Check this out....
                  Bobby

http://www.superchevy.com/how-to/transmission/1502-how-to-use-tremec-driveline-angle-finder-app/

[Steve Passmore]

I had the same problem on y 59 years back. The carrier bearing looked fine but at the end of a lot of searching it was the carrier. the rubber holding the bearing was rotted away. New bearing and housing cured it.

[59-in-pieces]

Ken,
My experience is, more often than not it ends up being the center barring and support bracket assembly, where the 2 halves of the drive shaft come together inside the "X" frame section - as Steve Passmore suggests.
This is particularly true if the drive shafts have been removed from the car, along with the assembly.
Because, unless you know, or saw them when removing the assembly, there are metal shims under the assembly and the inside of the "X" portion of the frame. See diagram (please excuse the spelling)
The shims are rectangular in shape with 2 slots half way through to accommodate the 2 mounting bolts through the frame to the assembly.
It's usually filthy greasy oily inside the frame in that area, and so the shims are easily left behind when the assembly is removed.
But, when installing the assembly, the shims can be easily scooted along and no longer in the proper alignment between the assembly and the frame.
re-positioning the shims could be your answer to solving the vibration problem.
IMHO.
Have fun,
Steve B.

[kkarrer]

Gentlemen,
      Thanks for the quick and interesting replies.  I'll get on it this weekend.  I'll let you know the results.
Take care,
Ken