[rotorwrench]

The C-O-M transmissions were available in small (FX), medium (MX), and large (HX) case versions. The FMX was the merger of the medium case components into an aluminum case that was much like one of the small case designs so they mated FX with MX to come up with the FMX. The FMX was the final type of the series. The AOD also has the Ravigneaux type planetary system but that's about all it shares with the older FMX & COM series other than the use of throttle correlation for shift control.

Some of the later cast iron case MX types still had the same type rear support but the rear pump fluid transfer components were deleted. I used one of these cases to set up a decent transmission for a 64 T-bird that I used to own. I never pulled the car anyway. It was too low. I pulled it backwards to get it home one time.