A trusted transmission shop is rebuilding the transmission in my 57 3100 column shift 3 speed. When they tore it apart they found that the main shaft is wallowed out and cannot be saved. They had a parts transmission out of a 58 but the main shaft in it had teeth broken off but did produce several other usable pieces for mine. At this point they said they would need to find a main shaft and they are unsure if their suppliers would have any.

I guess I'll begin searching around to see if I can find another transmission to use as parts. My question is what year range will the internal transmission parts interchange? How long did GM go before making changes? Also is there any difference between the 3 speeds in cars verses the truck?

As always I proud to be a part of the Stovebolt community. You guys are the best. Big thanks in advance.

Phoneman

1957 Chevy 3100 Telephone Installer\'s truck