[camino19]

1980 350/350t elky. Trans was fine for awhile, then son brought it home the other night and it wouldn't hold in drive. Almost like it is in 3rd gear. will shift manually, but will barely move from a stop in drive, and rolls backwards in drive on a hill. drop it into first and it moves just fine. Will upshift and down shift manually, but no automatic shifting. Any help is appreciated.

[tnsmith10]

Originally Posted by camino19

1980 350/350t elky. Trans was fine for awhile, then son brought it home the other night and it wouldn't hold in drive. Almost like it is in 3rd gear. will shift manually, but will barely move from a stop in drive, and rolls backwards in drive on a hill. drop it into first and it moves just fine. Will upshift and down shift manually, but no automatic shifting. Any help is appreciated.

well, from what you are describing, it seems as though you have 2 problems, vacuum unhooked from the trans or intake, and a sticky governor. if you had a broken governor gear, the trans wont shift at all, but a sticky governor will cause 3rd gear starts.
as for it shifting manually ok, with vacuum not hooked up, the trans will shift manually on both the 1-2 and 2-3 shifts with the modulator not getting any vacuum.
i do have a couple of questions though, first off, it you drive it with a heavy pedal, will it shift on its own? late and firm? and also, when you shift it manually, are you sure its shifting twice?
how many miles are on the trans? abd have you had any recent service work done recently?