In case of sliding mesh gearbox, the output shaft gears repeatedly rotate Together with the output shaft though in other gearbox, the output shaft gears are mounted with bearings that's why these gears rotates separately. Sensors in automatic transmissions use inner oil tension to shift gears at the appropriate time. https://gearbox-auto92580.loginblogin.com/41101005/top-latest-five-gearbox-auto-urban-news