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AMSOIL 25W-40 Synthetic-Blend Marine Engine Oil

Product code : WCMQT-EA

  • Excellent high-stress, high-rpm endurance
  • Increased rust and corrosion protection
Warning - Click here for Proposition 65 information for this product

AMSOIL 25W-40 Synthetic-Blend Marine Engine Oil



NMMAProtects Against Wear
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.

Excellent Anti-Rust Performance
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.

  • Excellent high-stress, high-rpm endurance
  • Increased rust and corrosion protection

NMMA Certified
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.

  • FC-W (CAT)® Registration Number: FC-11825T

* 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.

APPLICATIONS
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*.

  • API SM
  • NMMA FC-W Catalyst Compatible

SERVICE LIFE
Four-stroke outboard motors and personal watercraft: Due to potential fuel dilution or water contamination, change oil at the engine or watercraft manufacturer-recommended interval. Inboard and I/O applications: Change oil at two times the engine manufacturer-recommended interval, or once a year, whichever comes first.

WARRANTY
AMSOIL 25W-40 Synthetic Blend Marine Engine Oil is Warranty Secure®, keeping your factory warranty intact. It is a high-performance replacement for vehicle manufacturer-branded products and is also backed by the AMSOIL Limited Warranty (G1363). For details, visit www.amsoil.com/warranty/.

Warranty Secure

HEALTH & SAFETY
This product is not expected to cause health concerns when used for the intended application and according to the recommendations in the Safety Data Sheet (SDS). And SDS is available via the Internet at www.amsoil.com or upon request at (715) 392-7101. Keep Out of Reach of Children. Recycle used oil and bottle.

AMSOIL 25W-40 Synthetic-Blend Marine Engine Oil

Data Bulletin

Warranty

SDS



AMSOIL 25W-40 Synthetic-Blend Marine Engine Oil

  • 5 star rating
    Equal or superior
    By  TIM,  a  Verified Buyer  on  May 10, 2024
    Seems on par or superior to mercury oil. Will see next year when I change it but maintaining warranty and half the price of the alternative and a brand I trust is with the try.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product. Excellent customer service
    By  WILLIAM,  a  Verified Buyer  from  Mississippi  on  June 08, 2023
    Seems to perform better than oem oil. Fast shipping.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    It turned up and I put it in the boat
    By  Candid ,  a  Verified Buyer  from  Peterborough   on  May 28, 2023
    It is impossible for me to rate the quality and performance of this engine oil as it would require equipment, technology and scientific knowledge that I do not possess. The only thing I can say is that it turned up and I put it in the boat. Anything beyond that would be speculation on my part (Rating - I don’t know; Would I recommend- I don’t know). If Amsoil wishes I can send them a sample of the oil at the end of the boating season and they can run the appropriate tests to determine if the oil is still functioning to their specifications. Review complete!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent
    By  ALEX,  a  Verified Buyer  from  B.C.   on  May 24, 2023
    Originally I was using too light of an oil and I went to this 25W40 and was very happy with the oil pressure increase and now it doesn’t seem to go through any oil. Big block Chevy
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 3 star rating
    Oil and Oil fileter
    By  TOM,  a  Verified Buyer  on  May 19, 2023
    The oil is awesome. Customer service SUCKS! I called and asked 3 times on the live chat to get info for an oil filter for my Merc Pro XS 150.....NO RESPONSE!. Check your owners manual and then go a Merc rep to get the oil filter. Apparently AMSOIL doesn't update or do any type of referencing when looking up parts that we can service ourselves
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    BEEN USING THIS 25W-40 SINCE it has been offered
    By  MICHAEL,  a  Verified Buyer  from  Long Island NY.   on  March 09, 2023
    Great Oil. Have used it on my 1998 7.4 MPI Bravo 3 since it was first offered. Very little oil consumption. No smoke; engine have been running great with good oil pressure at idle at operating temperature.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Security on the water
    By  JEFF,  a  Verified Buyer  from  Colorado  on  November 23, 2022
    We've used Amsoil in both of the boats we've had and neither one ever had any issues. They quietly fire right up and purr like a kitten going across the water. I'll never use anything else.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best you can get
    By  ERIC,  a  Verified Buyer  from  Vermont  on  August 16, 2022
    I trust all of Amsoil products and I am using this in my Mercuriser IO cheaper than Quicksilver and I'm sure its a much better oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great stuff!
    By  JOHN,  a  Verified Buyer  on  May 06, 2022
    Engine runs smooth.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Marine Oil
    By  BRIAN,  a  Verified Buyer  from  Granum Alberta  on  April 14, 2022
    My 150 Merc runs smooth and and cool
    Bottom Line
    Yes, I would recommend this to a friend.
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