AMSOIL’s philosophy is to provide customers premium protection while still comporting to OEM recommendations in owner’s manuals. AMSOIL 25W-40 Synthetic-Blend Marine Engine Oil is formulated specifically for Mercury* and Mercruiser* motors that encourage the use of synthetic-blend oil. Mercury owner’s manuals actually discourage the use of full-synthetic oil. Since Mercury is the market leader and most Mercury owners won’t consider straying from these guidelines, AMSOIL 25W-40 Synthetic-Blend Marine Engine Oil was developed to give Mercury and Mercruiser owners a high tech upgrade while paralleling Mercury recommendations.
Use in gasoline-fueled four-stroke inboards, outboards, inboard/outboards and personal watercraft that require any of the specifications listed below, including those made by Mercury* and Mercruiser*.
AMSOIL 25W-40 Synthetic Blend Marine Engine Oil is certified by the National Marine Manufacturers Association (NMMA) for use in four-stroke outboards, inboards, stern-drives (inboard/outboards) and PWC. This high-quality oil demonstrates outstanding performance and exceeds the NMMA “FC-W” (Four Cycle – Water) specification requirements.
Engine performance and reliability are key to a successful day fishing or boating. High-rpm operation and constant exposure to water, however, invite engine wear and formation of rust and corrosion, reducing engine performance and life. AMSOIL 25W-40 Synthetic Blend Marine Engine Oil guards against wear while delivering excellent protection against rust and corrosion. It is Warranty Secure® and will not void your marine engine’s warranty.
Marine engines are prone to rust and corrosion due to constant exposure to humid, wet environments. Rust on engine parts acts like sandpaper, scouring bearings, the cylinder wall, piston rings and other components, while aluminum pistons and other parts can corrode. Rust and corrosion reduce engine power and eventually cause catastrophic failure.
Good rust protection is not natural to motor oil; it comes only by design. AMSOIL 25W-40 Synthetic Blend Marine Engine Oil is fortified with potent inhibitors that guard against damaging rust and corrosion.
Marine engines operate under high loads and rpm for extended periods. On average, a marine engine powering a boat 30 mph runs at about 5,000 rpm. In contrast, an automotive engine powering a car 60 mph runs at about 2,000 rpm. Higher stress causes traditional automotive oils to break down and lose viscosity. AMSOIL 25W-40 Synthetic Blend Marine Engine Oil is designed with excellent shear stability to deliver a consistent lubricating film. It helps guard engine components from wear for maximum life.
* All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are AMSOIL-engineered for use in the applications shown.
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