Propshaft Picture. Epicyclic gears. Sliding mesh gearbox. Prop-shaft. Universal and constant velocity joint. Clutch components 2. Basic explanation of a synchromesh. Detente device. Dog clutch. Constant mesh gearbox. Rzeppa joint. Dog clutch. Synchromesh unit. Helical gear advantage and disadvantage. Syncromesh Unit (Info) Double helical gear advantage and disadvantage. Interlock device. Clutch components. Four-wheel-drive layout.