Handbook transmissions need Energetic equipment shifting work by the driver using the clutch and gearstick As outlined by driving conditions. The handbook valve is what the shift lever hooks up to. Based on which gear is chosen, the manual valve feeds hydraulic circuits that inhibit specified gears. As an example, https://arthurkjgav.bloguerosa.com/33123349/gearbox-auto-can-be-fun-for-anyone