This product has been superseded by: 61N-45300-01-8D

Yamaha - Lower Unit Assembly - Drivetrain Component - 61N-45300-00-4D

Overview

The lower unit is responsible for transferring engine power down to the propeller, and when it starts to wear out, you’ll notice it right away—rough shifting, vibration, or inconsistent performance. The Yamaha Lower Unit Assembly 61N-45300-00-4D is built to restore smooth operation and reliable power delivery. Precision-engineered to meet OEM standards, it ensures proper alignment, efficient performance, and long-lasting durability in demanding marine environments.

Key Features

• Smooth Power Transfer – Delivers consistent propulsion from engine to propeller.
• OEM Yamaha Fitment – Built to factory specifications for precise alignment and installation.
• Heavy-Duty Gearcase Design – Designed to handle demanding marine use and engine loads.
• Corrosion-Resistant Construction – Performs reliably in both freshwater and saltwater environments.

Engine & Boat Compatibility

• Compatible with select Yamaha outboards (confirm fitment by model and year)

FAQ

Q: What are signs the lower unit needs replacement?
A: Grinding noise, slipping gears, or water contamination in gear oil are common indicators.

Q: Can I rebuild instead of replacing it?
A: Minor wear can sometimes be repaired, but major internal damage usually requires full replacement.

Q: Will this improve performance right away?
A: Yes, smoother shifting and better power delivery are noticeable after installation.

Q: Is this suitable for saltwater use?
A: Yes, with proper maintenance, it performs well in saltwater environments.

• Supersessions
  61N-45300-01-8D, 61N-45300-01-8D