AMSOIL Full Synthetic 0W-40 Motor Oil

AMSOIL 0W-40 synthetic oil is formulated with advanced technology to create the finest motor oils for people who demand maximum preservation and performance for their engines. The result is engine protection that surpasses even the most stringent industry benchmarks. Choose from the formulations below for oil that best meets your needs.

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  • AMSOIL Signature Series 0W-40 100% Synthetic Motor Oil

    A New Level of Motor Oil Technology

    • 75% more engine protection against horsepower loss and wear.1
    • 50% more cleaning power vs. AMSOIL OE Motor Oil
    • Protects turbochargers 72% better than required2 by the GM dexos1 Gen 2 specification.
    • 28% more acid-neutralizing power than Mobil 1.3
    • Trusted by professional engine builders
    • Guaranteed protection for up to 25,000 miles or 1 year

    1Based on independent testing of AMSOIL Signature Series 0W-20 using the ASTM D6891 standard test.
    2Based on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
    3Based upon independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896. Oils purchased in July 2020.

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  • AMSOIL Signature Series 0W-40 100% Synthetic Max-Duty Diesel Oil

    • Outstanding extreme-pressure protection
    • Delivers 6X more wear protection1
    • Maintains proper viscosity (thickness)
    • Minimizes oil consumption
    • Maximizes fuel efficiency
    • Excels in extreme temperatures
    • Confidently extend drain intervals

    1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation

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  • AMSOIL OE 0W-40 100% Synthetic Motor Oil

    • Fights sludge and deposits with 100% synthetic formulation.
    • 47% more wear protection1 than required by the GM dexos1 Gen 2 specification.
    • 100% protection against LSPI2 in the engine test required by the GM dexos1 Gen 2 specification.

    1Based on independent testing of OE 0W-20 in the Peugeot TU3M Wear Test as required by the dexos1 Gen 2 specification.
    2Based on zero LSPI events in five consecutive tests of AMSOIL OE 5W-30 Motor Oil in the LSPI engine test required by the GM dexos1 Gen 2 specification.

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  • AMSOIL Formula 4-Stroke® Powersports 0W-40 Synthetic Motor Oil

    • Specially formulated for four-stroke powersports engines
    • Delivers quick startup protection
    • Helps prevent carbon/varnish formation
    • Easy cold-weather starts
    • Wet-clutch compatible
    • Anti-rust fortified for superior rust protection
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  • AMSOIL 0W-40 FS 100% Synthetic European Motor Oil

    • Designed for the unique demands of gasoline, diesel and hybrid European vehicles.
    • European formula features precise blend of synthetic base oils and premium additives.
    • Exceptional engine protection without harming emissions systems.
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