I have 67 coupe with a c4 trans that no longer works in reverse. It drives fine but reverse stopped working. For a while it would leak fluid in when in reverse. I put the car away for winter. When I went to get it out for spring, no reverse. I found the bracket loose that holds the linkage to the transmission, one of the 2 bolts was missing, fixed that. It seems like it goes in to reverse, but does nothing but leak fluid on the floor. It is the original transmission, never been rebuilt, car has 73,000 original miles. Probably needs a rebuild after all this time, but would like to drive it in the mean time. Fluid level in trans is good. Just not sure if the forward gears are next? Perhaps the linkage is out of adjustment? Is there a seal on the shifter shaft that can be replaced to stop the leak when in reverse? Other causes that would make reverse not work?
Thanks, Paul

 

1st and reverse use the same gear, so if you have first gear, then it's a band apply failure.
The leak must be at the servo, coming out of the cover or crack in the case there. Since
the fluid leaks, there is no pressure to the servo, the reverse band cannot apply.

 

Just swap in a different C4, they are a dime a dozen. Easy peazy.

 

Reverse is always the first gear to go out. It's going to need to be gone through.