Mercury – Complete Gearcase | Bravo One XR / One XZ Series | Corrosion-Resistant Alloy | 8866A62

Overview
There’s something reassuring about a boat that responds instantly when you nudge the throttle. No drag, no hesitation — just a clean push as the hull settles into its groove. When you depend on that kind of feel, especially at higher speeds or in rougher conditions, the gearcase becomes the heart of your sterndrive system. The Mercury Marine part number 8866A62 Complete Gearcase restores that confidence. It’s built for boaters who expect their Bravo One XR or One XZ setup to run hard, run clean, and stay dependable no matter how many hours they put on the water.

Key Features

• Complete replacement gearcase for MerCruiser Bravo One XR (1.50 gear ratio) and Bravo One XZ (1.36 and 1.50 gear ratios)

• Tri-Paint corrosion-resistant finish designed for harsh marine environments

• XK360 low-copper alloy engineered to combat long-term corrosion

• Heavy-duty forged gears and reinforced U-joint for exceptional durability

• Designed to match OEM tolerances for a clean, precise fit

Engine & Boat Compatibility

• Compatible with MerCruiser Bravo One XR sterndrives (1.50 gear ratio)

• Compatible with MerCruiser Bravo One XZ sterndrives (1.36 and 1.50 gear ratios)

• Ideal for performance boats, speed-focused sport hulls, high-output recreational boats, and offshore cruisers

• Works in both single-engine and twin-engine sterndrive configurations

Performance & Practical Benefits
If you’ve ever felt a slipping shift or a sluggish response from a worn gearcase, you know how much it can change the personality of the boat. With the 8866A62 installed, everything feels tight again — the kind of tight that gives you confidence to lean into the throttle without second-guessing what’s happening below the transom. Acceleration becomes cleaner. Handling feels truer. Even simple maneuvering around the dock gains a level of smoothness that reminds you why Mercury’s engineering has such a loyal following.

Durability is where this gearcase really earns its place. The forged gears are built to take the punishment that high-performance boats deliver, while the corrosion-resistant coatings and low-copper alloy work together to shield the housing from what saltwater tries to do over time. It’s built to survive hard weekends, long runs, and constant exposure without losing its steady, reliable feel. Installation is straightforward for a complete unit like this, and once it’s mounted, you can almost feel your boat breathe easier — ready to get back to the water without hesitation.

Why Buy OEM
A gearcase isn’t the spot to cut corners. When you choose a genuine Mercury Marine part, you’re choosing precision engineering that matches your sterndrive exactly as it was designed. Everything aligns the way it should — from the internal gear geometry to the exterior coating thickness. Aftermarket versions might promise savings, but they rarely offer the same strength, corrosion resistance, or long-term smoothness. With OEM, you know the part is built to fit right, perform right, and last. If you want fewer surprises and more reliable hours on the water, OEM is the practical choice every seasoned boater will recommend.

FAQ
Q1: Which systems does the Complete Gearcase 8866A62 fit?
It fits MerCruiser Bravo One XR drives with a 1.50 gear ratio and Bravo One XZ drives with either a 1.36 or 1.50 gear ratio.

Q2: What makes this better than aftermarket gearcases?
The materials and engineering. Mercury’s forged gears, Tri-Paint finish, and corrosion-resistant alloy deliver durability aftermarket units rarely match.

Q3: How do I know if this is the correct replacement?
Confirm your sterndrive model (Bravo One XR or XZ) and gear ratio. If those align, this part number is typically the correct fit.

Q4: Can it be used in both saltwater and freshwater?
Definitely. It’s designed for harsh saltwater conditions, so freshwater performance is well within its range.

Q5: Is installation straightforward?
Yes. As a complete assembly, installation follows standard Bravo One procedures and fits cleanly when matched to the correct drive model.