Sierra 25W-40 FC-W Catalyst Compatible 4-Stroke Marine Engine Oil – 1 Qt
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Sierra 25W-40 FC-W Catalyst Compatible 4-Stroke Marine Engine Oil – 1 Qt
Keep your inboard or sterndrive engine properly protected with an oil that meets NMMA FC-W Catalyst Compatible certification. This 25W-40 formula is engineered for modern four-stroke marine engines — whether or not they're equipped with an emission catalyst system — and delivers the wear protection, corrosion resistance, and thermal stability needed for a full season on the water.
The 1-quart size is ideal for topping up between oil changes, keeping a spare aboard, or completing a partial service where you don't need a full multi-quart fill.
Key Benefits
- NMMA FC-W Catalyst Compatible — safe for engines with or without emission catalyst systems
- Industry-leading wear protection and deposit control for long engine life
- Enhanced detergent and dispersant properties prevent sludge formation
- Minimizes internal engine corrosion in freshwater and saltwater environments
- Reduces engine friction for improved efficiency
- Premium base stocks resist thermal and oxidative breakdown under sustained load
- Highly shear-stable viscosity prevents excessive thinning at operating temperature
- Advanced ZDDP anti-wear additive technology protects against phosphorus depletion and extends catalyst life
Specifications
- Viscosity: 25W-40
- Certification: NMMA FC-W Catalyst Compatible
- Volume: 1 Quart
- Engine Type: 4-Stroke (gasoline inboard & sterndrive)
- Application: Inboard & Sterndrive engines with or without catalyst systems
Related Products
- Sierra 25W-40 FC-W Catalyst Compatible Marine Engine Oil – 5 Qt
- Sierra 25W-40 FC-W Catalyst Compatible Marine Engine Oil – 55 Gal Drum
- Sierra Synthetic Blend 25W-40 FC-W Marine Engine Oil – 1 Qt
- Sierra Synthetic Blend 10W-30 FC-W Outboard Engine Oil – 1 Qt
Parts Desk Insights
The 1-quart size is best suited for topping up oil levels between scheduled changes, or as a spare to keep aboard in case you need to add oil mid-season. If you're doing a full oil change on a single inboard or sterndrive engine, the 5-quart jug is the more practical and economical choice — most MerCruiser and Volvo Penta engines require 4–6 quarts per service. The FC-W Catalyst Compatible designation is critical for newer sterndrive engines equipped with catalytic converters; using a non-compatible oil in these engines can shorten catalyst life. Check your engine owner’s manual to confirm the correct oil specification before purchasing.
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.