Yamaha - Lower Unit Assembly Gearcase Component 6CE-45300-05-8D. Overview. The Yamaha Lower Unit Assembly 6CE-45300-05-8D is built to deliver strong, consistent power transfer and reliable performance for high-horsepower Yamaha outboards. This assembly is what converts engine output into smooth propulsion, so when it starts to wear, you'll feel it immediately-vibration, noise, or reduced efficiency. Designed for demanding marine conditions, it restores performance and keeps your engine running at its best.. Key Features. • High-Performance Power Transfer - Ensures smooth propulsion and responsive handling.. • OEM Fit Precision - Engineered to Yamaha specifications for seamless installation and alignment.. • Complete Gearcase Assembly - Pre-assembled for dependable operation and easier replacement.. • Corrosion-Resistant Construction - Built to withstand harsh saltwater and freshwater environments.. Engine & Boat Compatibility. • F250DET1X 2010• F250XCA 2010-2020• F225XCA 2010-2020• F22