I have had several 65-66 Mustangs and I don't think any of them had the kickdown setup on them. It has never been an issue but I am looking at a new C-4 from TCI and they all state that the kickdown must be installed and working to prevent transmission failure. Is this true? Is the kickdown that necessary? I just manually downshift if I need to. Also, anybody have anyexperience with TCI?

 

I would drive a C4-equipped Mustang without the kickdown, but only as long as it takes to get the missing parts from my Mustang parts supplier.

If you have the throttle assembly with the downward-pointing arm for the kickdown, it's not even expensive to complete the kick.

This is the generic setup. The "six cylinder" cable operated type was used on V8 (289 and 390) from 66-68. Easy to install, easy to adjust, a gas to drive.

http://www.gerlecreek.com/images/65-66mustaccellink.jpg

 

It should not be an issue, but if you are going to invest in a new tranny you should do it right and get the kickdown and all. I bought a Lokar Kickdown cable for mine and it is a very nice piece.