Regular gearboxes usually have two sets of gears: enter and output. the input & the output. The enter gears are preset to the countershaft, creating them solitary units. It drives the person gears on the main shaft, which rotate freely on the bearings. Torque converter does the same functionality https://gearbox97429.thelateblog.com/34302600/a-simple-key-for-gearbox-unveiled