400 trans question

[kevin]

i just rebuilt my first 400 to go in my 77 grand prix.my problem is that it wont take off in 1st.you can manually put it in first and shifts good.i tried a diff. gov. and it worked untill i came to a stop.then it tried taking offf in 2nd.if you stop and put it in rev. or park then it takes off in 1st.can someone please give me some ideas? thanks
kevin

 

[chris718]

maybe you neglected to install the governor screen and it is causig each working governor you install to get stuck.i also speculate that there is a vbody problem or crossleak.using manual low allows additional oil to backshift the 1/2 shift valve there by opening up the idea of a pressure loss or overcharging caused by a crossleak.also is the intermediate band relined and too thick?did you change it?are the second gear clutches too tigtht.?engine breaking in d2?stuck kickdown solenoid?

 

[kevin]

i drove the car and it started working right.guess i'll keep my fingers crossed!!! thanks for your help and if something goes wrong i'll take a look at what you said.
kevin