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Sierra 18-2104 Heavy Duty Marine U-Joint Universal Joint

Manufacturer

Sierra

<p>For nearly six decades, Sierra has established itself as one of the marine industry's most trusted names in aftermarket engine and drive parts. Founded as a specialized marine parts manufacturer, Sierra has grown into a comprehensive supplier of replacement components, instrumentation, and accessories for both recreational and commercial boating applications. Operating from their 300,000-square-foot distribution center in Litchfield, Illinois, Sierra serves boat owners and marine technicians worldwide with an extensive catalog of parts engineered specifically for the harsh saltwater environment.</p><h3>Marine Engine Excellence</h3><p>Sierra's reputation was built on delivering precision-engineered internal engine components and drive system parts that meet or exceed OEM specifications. Their <a href="/7570-sierra-engine-gasket-set-5404">engine gasket sets</a> provide critical sealing solutions for inboard and outboard motors, while their <a href="/7570-sierra-engine-complete-assembly-15341">engine complete assemblies</a> offer comprehensive replacement options for major overhauls. Each component undergoes rigorous testing to ensure reliability in demanding marine conditions, from corrosion resistance to temperature cycling performance.</p><h3>Instrumentation and Monitoring Systems</h3><p>Accurate instrumentation is essential for boat operators to monitor engine health and prevent costly breakdowns on the water. Sierra's comprehensive line of <a href="/7570-sierra-gauges-200483">gauges</a> includes everything from fuel pressure and temperature indicators to voltmeters and trim gauges, all designed with marine-grade materials that withstand vibration, moisture, and UV exposure. Their <a href="/7570-sierra-tachometer-gauge-1488">tachometer gauges</a> deliver precise RPM readings critical for optimizing engine performance and fuel efficiency. Supporting these instruments, Sierra's <a href="/7570-sierra-gauge-resistor-47908">gauge resistors</a> ensure proper signal conditioning and accurate readings across various sensor types and engine configurations.</p><h3>Expanded Product Portfolio</h3><p>In 2022, Sierra significantly broadened its scope beyond traditional marine engine parts to encompass a wider range of boating accessories and even outdoor power equipment components. This strategic expansion brought established marine brands like Shields and Moeller under the Sierra umbrella, creating a one-stop resource for marine maintenance and replacement parts. The company now offers fuel systems, electrical components, battery charging solutions, and NMEA electronics alongside their traditional engine parts lineup.</p><h3>Quality Backed by Industry-Leading Warranties</h3><p>What sets Sierra apart in the crowded aftermarket marine parts market is their commitment to standing behind every component they manufacture. Their warranty coverage extends beyond simple part replacement—it includes shop labor, haul-out fees, towing charges, and related incidental costs should a warrantied part fail. This comprehensive protection reflects the company's confidence in their manufacturing processes and quality control standards. For boat owners facing repairs far from shore or mechanics working on customer vessels, this peace of mind is invaluable. Whether you're maintaining an outboard motor, rebuilding an inboard engine, or upgrading your boat's instrumentation, Sierra's decades of marine industry experience and commitment to quality make them a reliable choice for keeping your vessel running at peak performance.</p>

Part Number

118-2104
06/01/2036 5:58 AM
Sale Price

$38.14

In Stock (6)

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Usually delivered within 2 days

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No Hassle Returns

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Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-2104 is a heavy-duty universal joint (U-joint) designed for marine sterndrive applications. This Rockwell-style U-joint features robust construction with internal retaining clips and a 4-groove design, engineered to withstand the demanding conditions of marine environments while providing reliable power transmission between drive components.

Key Features:

  • Heavy-duty Rockwell-style construction for maximum durability
  • Includes both straight and 90-degree grease fittings for flexible installation and maintenance
  • Four-groove design with internal retaining clips
  • Greasable design allows for regular maintenance and extended service life
  • Direct-fit replacement for OEM components
  • Steel construction for strength and corrosion resistance

Applications:

  • Mercruiser MR-1 and Alpha-1 units (Serial Numbers 1684188 through B418818, approximately 1978-1990)
  • Mercruiser TR, TRS, and II SSM outdrives
  • OMC Cobra Drives (1986-1989)
  • Volvo Penta AQ200, 250, 270, 280, and 290 sterndrives

Replaces OEM Part Numbers: Mercruiser 36312, 41431, 58749, 75832, 758321, 75832A1, 75832A2, 75832A3, 75832T, 75832T1; OMC 912214, 915716; Volvo Penta 853255, 897707; GLM 28020; Mallory 9-72404

This Sierra Marine universal joint meets or exceeds original equipment specifications, providing reliable performance and peace of mind for your marine drive system repairs and maintenance.

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I have not installed the prop yet. But I did get it and it was not damaged.

Will buy from here again.

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