What year is my 904?

[NoGM4me]

My 71 Challenger has a 904 transmission with a VIN of 8A123456. How do I know if it's a 1978 or a 1968? It's still in the car and a grease ball so I can't find any other markings on it.
Thanks, NoGM4me

 

[tonysrt]

I think you may need numbers off the tranny to help you. The newer tranny, 78, would have a part throttle down shift were the older would have a full throttle downshift.

 

[moparleo]

Show us a picture of the pan rail. Cleaned off of course.