Yamaha - Lower Unit Assembly - Gearcase & Power Transfer - 64E-45300-02-8D

Overview

On these 150 to 200 horsepower Yamahas, the lower unit does a lot of heavy lifting, and when it starts to wear out, you can feel it right away. I’ve seen guys try to stretch them too long, but once gears start going, it’s better to swap the whole unit. This assembly brings things back to smooth, quiet operation with solid engagement every time you shift. It’s the kind of replacement that gives you confidence whether you’re cruising or pushing it hard.

Key Features

• Complete Gearcase Assembly – Includes internal gears and housing for a full lower unit replacement.
• Smooth Power Transfer – Delivers consistent engine output to the propeller.
• Corrosion-Resistant Construction – Built to handle saltwater and tough marine environments.
• Reliable Gear Engagement – Provides clean shifting with reduced noise and vibration.

Engine & Boat Compatibility

Fits Yamaha outboard engines in the 150 to 200 horsepower range. Commonly used on offshore boats, center consoles, and larger recreational vessels.

FAQ

Q: What are the signs that my lower unit is failing?
A: Grinding noise, slipping gears, water in gear oil, or difficulty shifting are all common signs.

Q: Can I keep running my motor if the lower unit is noisy?
A: It’s risky—continued use can cause more internal damage and lead to complete failure.

Q: Do I need to service the unit before using it?
A: Yes, always check and fill gear oil to the correct level before running.

Q: How does saltwater impact lower unit lifespan?
A: Salt can cause corrosion and seal wear over time, so regular flushing and inspection are important.

Q: Is this part still current or has it been updated?
A: This assembly has been superseded by part number 64E-45300-03-8D, which is the latest version.

• Supersessions
  64E-45300-00-8D, 64E-45300-01-8D, 64E-45300-03-8D, 64E-45300-04-8D, 64E-45300-04-8D