AMSOIL Full Synthetic Marine Motor Oil

Cast off with confidence using AMSOIL’s Synthetic Marine Oil, the trusted ally for boating enthusiasts. AMSOIL’s synthetic oil is specially formulated to provide your marine engine with superior protection against the harsh marine environment. It offers excellent anti-wear properties, rust and corrosion resistance, and maintains stable viscosity across a wide temperature range. Choose AMSOIL to keep your boat’s engine running smoothly and efficiently, whether you’re cruising calm waters or navigating choppy seas.

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  • AMSOIL 15W-40 Heavy-Duty Diesel and Marine Oil

    • Recommended for applications specifying API CI-4+ and prior specifications
    • Controls soot and wear
    • Reduces oil consumption and emissions
    • Delivers maximum engine protection over extended drain intervals
    • Provides outstanding protection and performance in temperature extremes
    • Try Signature Series Max-Duty 15W-40 for a serious upgrade
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  • AMSOIL 10W-30 100% Synthetic Marine Engine Oil

    • Excellent high-stress, high-rpm endurance
    • Increased rust and corrosion protection
    • NMMA FC-W Catalyst Compatible
    • Perfect for hardcore anglers and boaters who demand the best protection for their marine engines
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  • AMSOIL 10W-40 100% Synthetic Marine Engine Oil

    • Excellent high-stress, high-rpm endurance
    • Increased rust and corrosion protection
    • NMMA FC-W Catalyst Compatible
    • Perfect for hardcore anglers and boaters who demand the best protection for their marine engines
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  • AMSOIL 25W-40 Synthetic-Blend Marine Engine Oil

    • Excellent high-stress, high-rpm endurance
    • Increased rust and corrosion protection
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  • AMSOIL 75W-90 100% Synthetic Marine Gear Lube

    • Excellent gear and bearing protection, even when contaminated with 15% water1
    • Reduced friction and wear
    • Protection against rust and corrosion
    • Long seal life Superior foam prevention

    1Based upon AMSOIL testing of AMSOIL 75W-90 Synthetic Marine Gear Lube in ASTM 3233 and ASTM D892.

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  • AMSOIL 100% Synthetic 2-Stroke Injector Oil

    • Ideal for outboard motors and snowmobiles
    • Protects against rust and wear
    • Controls deposits
    • -60°F (-51°C) pour point
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  • AMSOIL HP Marine® 100% Synthetic 2-Stroke Oil

    • Excellent for Evinrude* E-TEC* factory-lean setting
    • Helps prevent deposits
    • Protects against wear
    • Low smoke
    • Protects against rust
    • Low aquatic toxicity
    • Superior performance as an injection oil or at 50:1 pre-mix
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  • AMSOIL 100:1 Pre-Mix 100% Synthetic 2-Stroke Outboard Oil

    Performance-Engineered for Outboards

    • Designed for pre-mix applications as lean as 100:1 ratios
    • Improves throttle response and lowers or eliminates smoke
    • Minimizes deposit formation and lowers emissions
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