Rebuilt C4 trouble

[kelbake]

Installed TCI overhaul kit in '72 C4. No automatic upshifting or downshifting. Have manual low and manual 2nd gear, rechecked valve body and governor. Performed air pressure checks to verify clutch and band operation. Only unusual indication was no 'thunk' heard when air pressure applied to Ford clutch passage. Any ideas?

 

[sportsroof69]

I rebuilt a C6 and had the same trouble, well sort of. My car wouldn't automatically downshift when I stopped, therefore, no auto upshift. It eventually fixed itself after a few hundred miles. No problems since. After the rebuild I put the car on jackstands and ran it through every gear for several minutes, but it still happened. I figure it had an air bubble or something.

 

[Ronstang]

It could be the governor, that is why I buy a new one (~$10) every time I rebuild a C4. You can take it apart and lightly polish the valvle and try that. Another symptom is a car that won't ever go into second, or third. I have had this happen and driving it for a little while worked it out.....governor again.

 

[10secgoal]

I had the same problem a few months ago when I rebuilt mine. It was all in the valvebody.(clutches work right ?) Then make sure the tranny is actually in the same gear as the shifter. (mine wasn't, thought I didn't have first after I actually fixed the problem.