Small Smooth Switching Lego Automatic Gearbox - YouTube
Sliding worm 3-speed automatic gearbox - LEGO Technic, Mindstorms, Model Team and Scale Modeling - Eurobricks Forums
A Simple LEGO Automatic Transmission | Hackaday
LEGO TECHNIC AUTOMATIC TRANSMISSION | Lego Technic | Experimenting with a LEGO Technic Automatic 4-speed Transmission – How can this be improved? Created by Sariel https://bit.ly/3fU26gn | By Beyond the Brick | Facebook
LEGO MOC 4 Speed Automatic Transmission with Rotary Catch by Lego3dPrinter | Rebrickable - Build with LEGO