I recently acquired a 1984 Thunderbird with a C4 transmission and was wondering how the C4 compared to the AOD from my 83 Cougar? I want to make sure that my cougar which is going to be my primary transportation has the best option available. I have no previous experience with either of them pros/cons so that is why I am asking here. Thanks much.
The C4 is a non-OD transmission and (basically) a non-locking C5 which was the predecessor to the AOD. If I were to put one in a daily driver, I'd go with the AOD.
The stock 84 three speed tranny is the C5.
I Based my statement on this http://www.crankshaftcoalition.com/wiki/Transmission_identification#Automatic_2 (http://"http://www.crankshaftcoalition.com/wiki/Transmission_identification#Automatic_2") because the transmission that came out of the t-bird matches up with the listed C4 here.