I have a swap done, L86 and 8L90 in a 67 Camaro. I had to buy the ECM and TCM separately from the drivetrain because they were not included. The ECM works fine but the TCM is setting codes. From what I understand it either needs the correct VIN and or 8L90 program with the specific solenoid info on the side of the trans case. Can anyone help me out? The GM dealer is saying they won’t flash a used TCM.
