Execution order
1. Disconnect the drive shaft from the gearbox.
2. Using a flat-head screwdriver, remove the sealing ring from the transmission housing.
Warning: Clean the O-ring seat and apply a thin layer of oil to it
3. Using drift 09431-21200, install a new O-ring into the transmission housing seat.
4. Lubricate the working edge of the new sealing ring with oil.