Re: GM transmission and push button shift.

Posted by HH56 On 2023/8/12 22:42:25

Mopar products and 57-8 Mercury used a mechanical system. Am not familiar with the Lincoln system but suspect it was like the Mercury. AMC also had pushbuttons but I believe they first used the Chrysler TorqueFlite transmission and Mopar button system and later on, a different system. Not sure which one. The mechanical pushbuttons operate a cam arrangement and each button incrementally moves a push-pull Bowden type cable which in turn moves the control valve in the trans valve body. In the cars with a Park selection, there is an interlock to kick out the other buttons but believe the Park paddle or button uses a separate cable that only controls that function. I think it would probably be rather difficult to adapt one of those mechanical systems to work the GM valve inside the trans and with the Packard steering column holding the not very spacious electric PB pod, also difficult there too.

Other than Packard, until the modern car era I believe the only other mfgs that used a full electric system is Edsel and Rolls Royce. When Packard went under and Edsel came along Autolite also built their system. Since they had built the Packard system Edsel was similar but re-engineered so most of the early teething issues Packard faced were eliminated. While the electrical is very similar they had a much more robust actuator and some redundancies. I don't have a photo of the actuator but articles mention and electrical diagrams show a better design for the finger and segment issues Packard faced. The Edsel shift motor is also stronger.

Rolls Royce has an actuator to work their version of the GM transmission which would bolt right on if there is room for it in the Packard frame. Electrically the RR system is very similar to the Packard system except they used micro switches operated by a lever instead of push buttons. It appears that it would be a simple matter to adapt the Packard PBs to work the RR actuator. Being RR, while the actuators are available on ebay they are not that plentiful and most rebuilt or at least claimed to work units are not cheap. I would be surprised if that is the solution Bendtsen mentioned.