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Sierra 18-1156 Marine Forward Gear Bearing

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

18-1156
09/12/2036 7:03 AM
Sale Price

$40.46

2 left at this price

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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 International 18-1156 is a precision-engineered forward gear bearing designed as a direct replacement for OEM components used in Honda and Mercury Marine outboard engines. This bearing supports the forward gear within the lower unit gearcase, ensuring smooth power transfer and reliable engagement during forward operation.

Sierra International is a trusted name in aftermarket marine parts, manufacturing components to meet or exceed original equipment specifications. The 18-1156 bearing is built to withstand the demanding conditions of marine lower unit environments, including exposure to gear lubricant, high rotational loads, and corrosive saltwater or freshwater conditions.

Key Features:

  • Direct OEM replacement — meets or exceeds original equipment specifications
  • Compatible with Honda outboard engines (OEM: 91051-ZW1-003)
  • Compatible with Mercury Marine outboard engines (OEM: 31-30894A1)
  • Precision manufactured for proper fit and long service life
  • Designed for forward gear/lower unit gearcase applications
  • Suitable for saltwater and freshwater use

The Sierra 18-1156 forward gear bearing is an ideal choice for marine technicians and DIY boaters looking for a reliable, cost-effective alternative to OEM parts. Always use the correct gear lube and follow manufacturer torque specifications during installation.

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It was fast and easy

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Good found what i needed

Easy to order. Good prices on shipping.

Price was very cheap. The cheapest I could find anywhere. Should be at my house soon. Very easy cite to navigate.

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