Ok so I recently completed my 4 speed swap in my 73 cuda. Put in a rebuilt 4 speed and all new linkage, clutch etc. Tried to drive the car and it would get stuck in 2nd gear. Put the car on jack stands with the car running and would shift like a champ! I adjusted the linkage to death and didn't make a difference one bit.
2 weeks ago I took the car to a transmission shop, they dropped the transmission, took it apart, said it looked decent and put it back together. After putting the transmission into the car it shifted beautifully on the car lift. Put the car on the ground and drove it around and it got stuck in 1st!
Replaced the shifter mechanism with a spare that a buddy had and produced the exact same symptoms. Anytime the car is sitting if shifts great.............put the car under a load and it gets stuck in gear every time. Any suggestions or ideas would be great we are baffled and frustrated. Thanks guys