The TH 400 had two different short tailshafts that I know of. The 66 Impala came with a TH 400 that had a short tailshaft and the OD of the yoke was small compared to the newer TH 400 yokes.
I am not sure of other years but I am sure of the 66 Impala. It almost sounded like he has the small yoke and the large short tailshaft. I just thought that it was unusual for a seal to fit the housing and not fit the yoke, especially since the transmission was just rebuilt.
Adam 12, please post what the solution turns out to be.
Good luck!
Jim
|