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AMSOIL 10W-40 100% Synthetic Marine Engine Oil

Product code : WCFQT-EA

  • 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
Warning - Click here for Proposition 65 information for this product

AMSOIL 10W-40 100% Synthetic Marine Engine Oil



Specially engineered for marine applications. Durable formulation protects in severe conditions, from all-day trolling to high-rpm operation. Heavily fortified with advanced additives designed to prevent deposits, rust and corrosion. Use in gasoline-fueled four-stroke inboards, outboards, inboard/outboards and personal watercraft, including those made by Honda,* Mercury,* Yamaha,* Johnson/Evinrude,* Bombardier/BRP,* Suzuki,* Nissan,* Tohatsu,* OMC,* Volvo-Penta,* Mercruiser,* Chevrolet* and Ford.*

See the Product Data Bulletin for full details.


FIGHTS ENGINE WEAR

  • Naturally strong base oils resist viscosity loss due to mechanical shear.
  • Develops a tough lubricating film that protects engine parts, even in high-heat, high-rpm conditions that break down other oils.
  • Contains robust anti-wear additives that further reduce wear in metal-to-metal contact regions, guarding against compression loss for maximum power and engine life.

EXCELLENT ANTI-RUST PERFORMANCE

  • Fortified with potent inhibitors that guard against damaging rust and corrosion.
  • Protects engines during use and during inactivity or long-term storage.

NMMA CERTIFIED

  • Certified by the National Marine Manufacturers Association (NMMA) for use in four-stroke outboard motors.
  • Demonstrates outstanding performance and meets the requirements of the NMMA FC-W Catalyst Compatible specification, which is backward-compatible with the FC-W specification.

See the Product Data Bulletin for full details.

*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.

AMSOIL 10W-40 100% Synthetic Marine Engine Oil

Data Bulletin

Warranty

SDS



AMSOIL 10W-40 100% Synthetic Marine Engine Oil

  • 5 star rating
    Marine oil
    By  SPENCER,  a  Verified Buyer  on  June 17, 2025
    Great oil and great for protection especially for my wave runner that runs at high RPMs all day.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great
    By  RAYMOND,  a  Verified Buyer  from  AK  on  May 19, 2025
    Great oil. No problems with any of my motor since I started using amsoil 25 years ago. Capt.Ray
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    4 stroke outboard oil
    By  BRIAN,  a  Verified Buyer  on  May 18, 2025
    Running the Amsoil/Wix combination in both of my Suzuki 250ss's. Great products and fast shipment for me, and an upgrade from the semi synthetic oil that the Ecstar is.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Good product
    By  RODERICK,  a  Verified Buyer  from  North Carolina  on  May 10, 2025
    This oil made my outboard run smoother!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil
    By  DALE,  a  Verified Buyer  from  Picton, Ontario   on  May 09, 2025
    I’ve been using this synthetic oil in my F115 Yamaha for years. My engine has been trouble free, averaging 95 engine hours per season!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    motor
    By  ANTHONY,  a  Verified Buyer  from  Port Colborne Ontario Canada  on  May 05, 2025
    most expensive oil in the world best oil in the world
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    motor
    By  ANTHONY,  a  Verified Buyer  from  Port Colborne Ontario Canada  on  May 05, 2025
    most expensive oil in the world best oil in the world use it in my 75hp Yamaha since it was new in 2003
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Marine engine oil
    By  MTP,  a  Verified Buyer  from  Hickory   on  May 03, 2025
    My Mercury 25 hp four stroke has a strict diet! And AMSOIL is what it craves!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Mercury Outboard
    By  GARY,  a  Verified Buyer  from  North Vancouver, BC  on  April 24, 2025
    Mercury outboard oils are a blend which I do not like. Prefer 100% synthetic for my engines.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    MERCURY RACING 525 WITH WHIPPLE
    By  KIRBY,  a  Verified Buyer  from  BULLHEAD CITY  on  April 11, 2025
    I HAVE CHANGED ALL OF MY FLUIDS OVER TO AMSOIL. THE BOAT ENGINE SEEMS TO FIRE UP QUICKER AND RUN MORE SMOOTHLY WITH THE AMSOIL MARINE 10-40. MANY FELLOW BIG MOTOR PEOPLE I KNOW STILL USE 20-50 OR STRAIGHT 50 IN THE HEAT ON LAKE MOHAVE AND HAVASU, BUT I HAVE FOUND IM STILL CONSISTENTLY AT 50 PSI OIL PRESSURE AT OPERATING TEMP AND AM HAPPY WITH THAT
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?