Mercury 150 HP Lower Unit # 8M0099221

OEM Mercury Lower Unit – 8M0099221 | 150 HP 4-Stroke | Extra Long Shaft

This OEM Mercury Marine Lower Unit (Part #8M0099221) is a genuine factory-built replacement designed specifically for 150 HP 4-Stroke Mercury outboards with an Extra Long Shaft configuration. Unlike aftermarket versions, this is a 100% Mercury-manufactured unit—precision-engineered and quality-tested to meet factory standards for performance, durability, and seamless integration with your outboard system.

Ideal for serious anglers, boaters, and marine professionals, this gearcase ensures maximum propulsion efficiency and reliability in demanding water conditions. Whether you’re replacing a damaged unit or upgrading for peace of mind, this Mercury 150 outboard lower unit is your top-tier solution.

If your boat requires a Long Shaft instead, ask our experts about available options. We’re here to ensure you get the exact fit your motor needs.

Features & Benefits:

• ✅ Genuine Mercury OEM Lower Unit – not aftermarket or rebuilt
• ✅ Designed for 150 HP 4-Stroke outboards – precision-matched gearing
• ✅ Corrosion-resistant marine-grade finish for saltwater or freshwater use
• ✅ Pre-assembled with internal components – plug & play installation
• ✅ 1-Year Manufacturer Warranty for peace of mind
• ✅ Eligible for core rebate – recycle your old unit and save money
• ✅ Fast shipping – available in-stock for immediate delivery

Pricing

Total Price: $4,195
Ask about core return rebate – refund varies by condition
Final Price: Contact us to confirm rebate eligibility

Product Finish:

• Black, corrosion-resistant OEM marine coating
• Matches factory-installed Mercury aesthetics and quality

Core Rebate Information

• ♻️ Ask about how to recycle your core & receive $ back
• Return your old core, get up to $200 back
• Rebate amounts vary based on condition of your core

Useful Resources

• 🔍 How to find your Boat Engine serial number?
• Still deciding? Watch our YouTube video How avoid common lower unit replacement mistakes.
• To help extend the life of your gearcase, check out our Boat Maintenance Checklist.