Order of execution
1. Disconnect the drive shaft from the gearbox.
2. Use a flat screwdriver blade to remove the O-ring from the gearbox socket.
Warning! Clean the O-ring seat and apply a thin coat of oil to it
3. Using drift 09431-21200, install a new o-ring in the transmission case housing.
4. Grease a working edge of a new sealing ring with oil. Gear Oil: SAE 75W-90 (API GL–4).