Fluid drive
Is the Fluid Drive a manual gear change with a torque converter instead of a clutch?
I used to have a 1974 Citroen GS 1220 with convertisseur transmission - a 3 speed manual with torque converter and an automatic clutch. It was fabulous to drive. When you pressed on the gear lever, it would electrically declutch the tiny wet clutch inside the torque converter, to make gear changes easier. When you released the gear lever, it would re-engage the clutch. You still had to release the accelerator pedal to change gears. When stopping, you would brake to a stop, change to first gear, the torque converter would slip to allow you to sit still with engine idling, just like a fully auto car. (clutch still engaged.) When you pressed the accelerator, the car drove just like an auto, till you had to release the accelerator and change to second gear. It was a lovely smooth car to drive, and despite having only a 1.2 litre, air cooled flat 4 engine, it could eat six-cylinder Holdens at the traffic light Grand Prix. I haven't owned that car since the 1980s but I'd love to own one now. My sister liked my car so much she bought one the same, though hers was a manual gear change 4 speed and was in much better condition than my car.
The video below (gizmo's link) shows the model I had, with the convertisseur transmission. The video is in French, you can select auto-generated English subtitles but they are very bad translations. Explanation of the convertisseur auto begins at 9.00 minutes. My car was right hand drive, so it had conventional round dials on the dashboard, not the amazing display in the French car.
The boot (trunk) you can see about 12:30 can hold a Hoover front load washing machine - just! - I speak from experience... it was a tight squeeze.
This link is to a technical explanation of the convertisseur transmission:
http://www.citroenet.org.uk/passenger-cars/michelin/gs/gs-18.html
This link is a better video of driving a GS convertisseur: