The Stovebolt Site Forums The Shop Area Driveline Saginaw 3-speed Overdrive Question

Member rfs56trk/Fred has an idea that I may be able to make a certain Ford solenoid into a solenoid that will fit and work for this GM transmission. I find that his idea does work. The Saginaw version of the Chevrolet overdrive transmission uses a solenoid that is made by Warner. Fred told me that the Ford solenoid is internally the same. I found that the plungers are interchangeable, so I installed the long plunger from the GM transmission into the Ford solenoid. There is one external difference. The diameter of the step in the mounting flange is bigger on the Ford version. The height is the same on both solenoids. I found that diameter on the GM solenoid to be 0.765". I found that diameter on the Ford solenoid to be 0.823". I machined that diameter on the Ford version to 0.765".

I have the NOS kickdown switch and this modified solenoid installed. The system passes the checks that are shown in the Ford overdrive manual.

We are forecast for rain/sleet/snow for the rest of this week. I do not drive this truck on wet days, so I will make a test drive next week. Below are the sketches of the measurements that I made.

Edit: I'm told that the solenoid that I used is not unique to Ford. I believe that any solenoid from that era that was made by Borg Warner (RBW) may work for this modification.