Yamaha - Gear 1 Assembly - Lower Unit Gear System - 6L5-45560-00-00

Overview

When a lower unit starts making noise or slipping under load, it usually comes down to worn internal gears. This is one of those parts that takes constant stress every time you throttle up or shift. I’ve seen engines feel completely different just by replacing a worn gear assembly like this. Once it’s in, everything runs smoother, quieter, and a lot more dependable.

Key Features

• Precision-Cut Gear Teeth – Ensures smooth engagement and efficient power transfer.
• High-Strength Construction – Built to handle torque and load without premature wear.
• Factory-Spec Fitment – Designed to match Yamaha lower unit tolerances for proper operation.
• Restores Drivetrain Performance – Helps eliminate slipping, noise, and rough operation.
• Wear-Resistant Finish – Engineered to withstand continuous contact and high-speed rotation.

Engine & Boat Compatibility

Designed for Yamaha outboard engines with compatible lower unit gear systems. Commonly used in small to mid-range outboards powering fishing boats, skiffs, and utility vessels. Always confirm part number compatibility before installation.

FAQ

Q: What are signs that this gear is worn out?
A: Grinding noises, slipping under load, or metal shavings in gear oil are strong indicators.

Q: Do I need to replace other parts at the same time?
A: It’s a good idea to inspect bearings, seals, and other gears while the unit is open.

Q: Is installation a simple job?
A: It requires opening the lower unit and proper setup, so it’s usually done during a rebuild.

Q: Can this cause vibration while running?
A: Yes, worn gears can create vibration and uneven power delivery.

Q: How does water intrusion affect this part?
A: Water in the gear case reduces lubrication and can quickly damage gear surfaces.