Modern autos use helical gears and synchromesh equipment inside the gearboxes, that synchronize the rotation of gears that are about to mesh. This removes clashing with the gears and will make equipment shifting simpler. Torque converter does precisely the same function the clutch does within the handbook gearbox method. https://landeniqvfq.therainblog.com/32726759/the-2-minute-rule-for-gearbox