Piston de boîte de vitesses

A gearbox (transmission) is the assembly of gears and shafts that changes the ratio between the engine and the drive wheels.

By engaging different gear pairs it trades speed for torque, letting the engine pull a heavy load from rest and run efficiently at speed; the housing also holds the lubricating oil.

The gearbox sits between the clutch and the propeller shaft. The correct part matches the specific gearbox model.