18-4231 SIERRA, OMC "PROP THRUST WASHER" Replaces 320570

# 18-4231 SIERRA, OMC PROP THRUST WASHER Heavy-duty thrust washer engineered to manage axial loads in propeller shaft assemblies. This OEM-equivalent component distributes propeller thrust evenly across the gearbox, preventing premature wear and bearing damage. Direct replacement for OMC part 320570, compatible with Sierra-equipped marine engines. Precision-manufactured from marine-grade materials to resist corrosion and maintain dimensional stability under extreme operating pressures. Critical for smooth propeller engagement, efficient power transfer, and extended drivetrain longevity in saltwater environments.