Dave, the MoPar system used a fluid coupling bolted to the crankshaft, with a conventional manual clutch on a flywheel-like plate at the output of the fluid drive. There were both regular 3-speed versions and the semi-automatic 4-speeds. The fluid drives had their own reservoirs in some applications, while others used engine oil, circulated from the crankcase by the engine lubricating system. I remember a 53 Plymouth driven by a co-worker that took 9 quarts of oil on a change when both the crankcase and the clutch reservoir were drained. The mechanical seal on the fluid drive units had a nasty habit of leaking, and it was a real PITA to replace one. As I remember, some of the semi-auto transmissions weighed close to 200 pounds!
Jerry
