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Sierra 18-9420-7 10W-30 FC-W 4-Stroke Outboard Motor Oil 55 Gallon Drum

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

18-9420-7
09/12/2036 5:54 AM
Sale Price

$1,975.77

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

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Fitment guaranteed

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Product Details

Sierra 18-9420-7 is a premium 10W-30 four-stroke outboard motor oil specifically formulated to meet or exceed the stringent requirements of leading marine engine manufacturers including Mercury, Yamaha, Johnson-Evinrude, Suzuki, and Honda. This professional-grade marine oil is NMMA FC-W® Certified and comes in a bulk 55-gallon drum for high-volume applications.

Key Features:

  • Excellent anti-wear characteristics protect critical engine components
  • Formulated to offer maximum corrosion protection in harsh marine environments
  • Reduces sludge buildup and keeps engines cleaner for better efficiency and performance
  • Low temperature viscosity provides better cold starting in cooler conditions
  • Meets and exceeds API SJ, CF-2, and CH-4 quality performance standards
  • NMMA FC-W® Certified for marine four-stroke applications

Designed for commercial marine applications, boat dealerships, and high-volume users, this 55-gallon drum provides economical bulk storage of quality four-stroke outboard oil. The advanced formulation protects against wear, corrosion, and deposit formation while maintaining optimal engine cleanliness and performance across a wide range of operating conditions.

Products specifications

Grade

10W30

Size

55 Gallon

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The site was awesome to use and the prices are great as well. All of my items came undamaged though one of my drum brakes arrived dusty and unwrapped in its box- but it was still in good condition. My only complaint is that my order was all set to arrive by the Friday before Christmas and pieces of my order didn't arrive until after Christmas. Also online it says that those particular items didn't ship (maybe that factory was just slow to update their tracking info). I tried to contact autoplicity, but they were understandably closed for the holidays then by the time they reopened my order was already in hand. Overall, the pros outweigh the one con and I will order from them again.

Quick delivery and correct parts Good service

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The box was badly damaged on reciept , and the flange on the filter was bent . Other than than the service was good .

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Best price I could find! Great customer service kept me informed through the whole order process to insure acuracy since it was being sent directly from the manufacture. Recieved my order in good time, right parts and no damage. Overall very satisfied and will be doing business again in the future.

very easy to find the parts I was looking for and for the right price. Shipping took longer than expected but worth the wait

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