Sierra High Performance Marine Gear Lube — 1 Quart | 18-9650-2
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Sierra High Performance Marine Gear Lube — 1 Quart
Sierra High Performance Marine Gear Lube is a premium SAE 90 hypoid gear oil formulated specifically for the demanding conditions of marine outboard and sterndrive lower units. It provides reliable lubrication and protection for gears, bearings, and seals in the lower unit — where high loads, water contamination risk, and wide temperature ranges make lubricant quality critical to long-term reliability.
This 1-quart (946 mL) size is the standard quantity for a lower unit service on most outboard and sterndrive applications. It meets or exceeds OEM specifications for major marine engine manufacturers including Mercury, Yamaha, Johnson/Evinrude, and OMC.
Key Specifications
- Volume: 1 quart (946 mL)
- Viscosity: SAE 90 hypoid
- Application: Outboard and sterndrive lower units
- OEM Compatibility: Meets or exceeds Mercury, Yamaha, Johnson/Evinrude, OMC specifications
- Part Number: 18-9650-2
Parts Desk Insights
Best Use Case: This gear lube is the correct choice for annual lower unit service on most outboard and sterndrive engines where the OEM specifies an SAE 90 hypoid gear oil. Changing the lower unit gear lube annually — or after any water intrusion event — is one of the most important and often overlooked maintenance tasks on a marine engine. Milky or discoloured gear lube is a sign of water contamination through a failed seal, and catching it early prevents catastrophic gear damage. One quart is the correct quantity for most single lower unit services; larger outboards or sterndrives may require two quarts — check your engine service manual for the correct fill volume before ordering. Always confirm your engine manufacturer’s gear lube specification before substituting an aftermarket product.
Note: Gear lubricants are considered a hazardous material for shipping purposes. Ground shipping only — not available for air freight.
Estimated Packaging: Bottle approximately 6" × 4" × 4" (15 × 10 × 10 cm), approx. 1.1 kg shipped.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.