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Sierra 18-6401 U-Joint Assembly for MerCruiser Bravo Stern Drives

Manufacturer

Sierra

<h3>Sierra: Six Decades of Marine Aftermarket Excellence</h3><p><strong>Sierra</strong> has spent nearly 60 years earning its reputation as one of the most trusted names in the marine aftermarket industry. Originally focused on engine and drive components for boats, the brand has grown into a comprehensive source for nearly everything a boater needs to keep their vessel running at its best — from precision instrumentation to complete engine rebuild hardware.</p><p>Now operating as a brand of Dometic, Sierra manages global aftermarket distribution from a 300,000 sq. ft. facility in Litchfield, Illinois. The Sierra brand today encompasses not only its flagship marine parts line but also well-established marine names like Shields and Moeller, offering boaters a broader catalog than ever before. Whether you own an outboard, inboard, or sterndrive, Sierra's engineering team designs products to meet or exceed OEM specifications.</p><h3>Precision Instrumentation You Can Trust on the Water</h3><p>One of Sierra's most recognized product areas is its marine instrumentation lineup. The brand's <a href="/7570-sierra-gauge-set-1480">gauge sets</a> cover everything from classic analog instrument clusters to advanced digital multi-function displays. Sierra offers packages suited to outboards, sterndrives, and gasoline-powered inboards, with options ranging from coordinated analog kits in styles like Arctic, Eclipse, and Amega to modern touchscreen solutions like the R3 multi-function gauge. Features such as scratch-resistant domed glass lenses, silicone-dampened pointers, and perimeter backlighting make these instruments highly readable in all conditions.</p><p>Behind every accurate gauge reading is a properly calibrated sending circuit. Sierra's <a href="/7570-sierra-gauge-resistor-47908">gauge resistors</a> are a critical part of that chain, ensuring the signals from sensors and sending units are correctly interpreted by your instruments. These components are built to marine-grade standards to resist moisture, vibration, and corrosion — the realities of life on the water.</p><h3>Engine Internals Built to OEM Standards</h3><p>Sierra's history in marine power is perhaps best demonstrated by its deep catalog of engine components. The brand's <a href="/7570-sierra-engine-gasket-set-5404">engine gasket sets</a> cover a wide range of outboard and inboard applications and are engineered to deliver reliable seals in the demanding thermal and chemical environment of a marine engine. For boaters performing seasonal overhauls, top-end rebuilds, or full engine restorations, Sierra gasket kits are a go-to resource trusted by professional marine technicians and DIY boaters alike.</p><h3>A Complete Marine Parts Partner</h3><p>Beyond instrumentation and engine internals, Sierra's catalog spans fuel systems, electrical supplies, steering components, shore power, and more — all covered by what the brand calls an industry-leading warranty. Sierra also maintains a comprehensive parts-finder tool that enables cross-referencing with OEM part numbers from major manufacturers including Mercury, Yamaha, Suzuki, Volvo Penta, and others, making it straightforward to find the right replacement part for virtually any application.</p>

Part Number

18-6401
09/12/2036 6:34 AM
Sale Price

$519.42

In Stock (6)

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Usually delivered within 2 days

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Product Details

The Sierra 18-6401 is a premium universal joint (U-joint) assembly engineered for MerCruiser Bravo stern drive systems. This critical drivetrain component ensures smooth power transfer from the engine to the propeller, providing reliable performance for your marine vessel.

Key Features:

  • Direct replacement yoke assembly for MerCruiser Bravo I, II, and III stern drives
  • Fits models from 1998-2005 with serial numbers 0B664190 and up (serial range 0B664190-0M111207)
  • GKN-style design utilizes external clips for secure u-joint retention
  • Replaces Mercury Marine part numbers 864244A2, 12784A10, and 12784A4
  • Cross-references with GLM part number 28060
  • Also compatible with MerCruiser Blackhawk drives (1993-1998)

This assembly serves as the replacement for the original Bravo Meritor assembly, with the key difference being the clip design—the Meritor version uses internal clips while this GKN-style uses external clips. Built to OEM specifications, the Sierra 18-6401 delivers the durability and precision required for demanding marine applications.

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The process was quick and easy. The cost was very reasonable.

Ok

great price, great stock

Sign up was quick and easy. Payment method was easy to find and use. Be careful, stock photo does not always show exact item you are buying. More info on product specs would also be helpful.

Easy To Order but Expensive Shipping

nice price!

Easily done, quick

Easy fast thanks

Don't know if it accepted the coupon code but shopping was easy.

Good job guy great parts

Excellent place to deal with. I am a returning customer and love the fast shipping!!

Simple and EZ

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