Yamaha - Propeller Shaft Lower Unit Shaft 6CF-45611-00-00. Overview. The propeller shaft is one of those parts you don't think about until something feels off in the water. It's what takes all that engine power and turns it into forward movement, so it has to be straight, strong, and reliable. I've seen bent or worn shafts cause vibration and poor performance that you can feel right away. When it's right, everything runs smooth and the boat tracks the way it should.. Key Features. • Direct Power Transfer Design - Delivers engine output efficiently to the propeller for smooth propulsion.• High-Strength Shaft Construction - Built to handle torque and load without bending or failure.• Precision Machined Fit - Ensures proper alignment within the lower unit for consistent operation.• Smooth Rotation Performance - Helps reduce vibration and improves overall handling.• Corrosion-Resistant Build - Designed to withstand harsh marine environments over time.. Engine & Boat Compatibility. Designed