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Sierra 18-1157 Forward Gear Inner Bearing for Mercury Marine & Honda Outboards

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

18-1157
08/05/2036 12:57 PM
Sale Price

$17.19

1 left at this price

delivery box

Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-1157 is a Forward Gear Inner Bearing designed as a direct replacement for Mercury Marine and Honda outboard lower unit gearcase assemblies. This aftermarket bearing is manufactured to meet or exceed the original equipment specifications it replaces, ensuring a proper fit and reliable performance in the marine environment.

Key Features:

  • Direct OEM replacement forward gear inner bearing
  • Meets or exceeds original equipment specifications
  • Designed for use in lower unit gearcase assemblies
  • Compatible with a wide range of Mercury/Mariner, Mercruiser, and Honda outboard applications from 30–250 HP
  • Manufactured by Sierra, the market leader in aftermarket marine engine parts

Replaces OEM Part Numbers:

  • Honda: 91057-ZW1-003
  • Mercury Marine: 31-30895, 31-30895T

Sierra International is a trusted supplier of aftermarket marine parts, providing comprehensive coverage across all major engine brands with an unsurpassed customer satisfaction warranty covering parts and labor.

Great place. Wish some idems had more detailed descriptions.

It took over 30 min to place this order. your pay site has problems.

the service is #1 they keep you inform of the status of your order the prices are lower than those e internet sites<br>they go against the best and come out winning.<br>

Exactly what I ordered for the best price and fast, too!

Ordered Sunday and recieved product Tuesday .. What more can u ask for? Great Seller!

so far so good

Your site looks professionally constructed and has an easy to understand interface.

Tank You!! Thank you very much

Very easy system. I hope the shipping is fast too.

Quick and to the point. No signing up for email newsletters and all that junk. Great shipping rates as well

Simple checkout process

Best price on the web (order#10369). Fast order and they had the products I wanted. Will recommend and purchase again from them.

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