Mercury – Complete Gearcase | Bravo Three / Three X Series | Corrosion-Resistant Alloy | 8M0046733

Overview

If you run a Bravo Three drive, you already know how much trust you place in the gearcase. It’s doing the hard work every time you ease into gear, trim up onto plane, or push through a tight turn with a crosswind. When a gearcase starts to fail, you feel it in your gut long before you hear it. That is why boaters who demand reliability turn to the Mercury 8M0046733 Complete Gearcase. It brings back that steady, predictable performance you count on—whether you’re running offshore with the family or cruising home after a long day on the water. There’s comfort in knowing the heart of your drive system is brand-new, built to Mercury specifications, and ready for years of abuse.

Key Features

• Replacement gearcase for Bravo Three and Bravo Three X sterndrives
• Supports both 1.36 and 1.50 gear ratios
• XK360 low-copper alloy for superior corrosion resistance
• Durable Tri-Paint system with a tough, long-lasting barrier
• Heavy-duty near-net forged gears for strength and longevity
• Engineered for seamless alignment and proper gear mesh

Engine & Boat Compatibility

Designed for:

• MerCruiser Bravo Three sterndrives (serial No. 0D784124 & up)
• MerCruiser Bravo Three X sterndrives with 1.36 or 1.50 ratios

Commonly used on:

• Cruisers and sport cruisers
• Offshore fishing boats
• Multi-engine center consoles
• Larger bowriders
• Houseboats and cabin boats running Bravo drives

Performance & Practical Benefits

The moment you install this gearcase, the whole drive system feels more confident and predictable. Shifts come through clean and smooth—none of that rattling hesitation you get from worn gearsets. The forged gears give you that reassuring, solid engagement every time you hit forward or reverse. And once you’re moving, the drive feels steady under load, even during sharp turns or when trimming up in sloppy conditions.

The corrosion resistance is another major benefit. Between saltwater, marine growth, and constant temperature changes, gearcases take a beating. Mercury’s XK360 alloy and the Tri-Paint coating work together to slow down corrosion, keeping the gearcase looking clean and performing strong season after season. It’s one of those upgrades that pays you back over time because you’re not constantly dealing with pitting or premature failures.

This gearcase also installs with the precision you expect from an OEM part. Everything lines up, the tolerances feel tight, and you won’t be fighting misalignment or strange vibrations. It’s engineered to restore your drive to factory performance—not “good enough,” but the genuine Mercury standard.

Why Buy OEM

A Bravo Three-series drive is not the place to experiment with cheaper aftermarket parts. The loads are too high, the tolerances too exact, and the cost of failure too expensive. An OEM Mercury Marine part gives you the same reliability and engineering your boat left the factory with. You get proven materials, proper alignment, long-lasting gears, and the peace of mind that comes from knowing your gearcase is built for your exact sterndrive—not “many models,” but your model.

It’s also the most cost-effective choice in the long run. You install it once, it fits right, and it performs the way Mercury intended.

FAQ

Q1: Which engines does this gearcase fit?

It fits Bravo Three and Bravo Three X sterndrives equipped with 1.36 and 1.50 gear ratios.

Q2: Why choose OEM instead of aftermarket?

OEM gearcases last longer, fit properly, and match Mercury’s precise engineering standards.

Q3: How do I confirm this is the right gearcase?

Check your sterndrive’s serial number and gear ratio—both must match the compatibility list.

Q4: Can it handle saltwater?

Yes. The alloy and Tri-Paint coating are designed specifically for harsh saltwater environments.

Q5: Is it difficult to install?

Most marine techs handle the job easily. Experienced boaters with proper tools can also install it confidently.