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AMSOIL 10W-40 100% Synthetic Marine Engine Oil

Product code : WCFQT-EA

4.9 star rating Read 127 reviews

Customer Rating

4.9

88% would recommend

  • 5 122
  • 4 2
  • 3 1
  • 2 1
  • 1 1

AMSOIL 10W-40 100% Synthetic Marine Engine Oil

4.9 star rating Based on 127 reviews
  • 5 star rating
    Smooth running
    By  DALE,  a  Verified Buyer  from  Picton, Ontario   on  November 29, 2024
    My Yamaha F115 outboard runs smoothly and efficiently. Been using this oil for the last 5 years, highly recommended!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Engine
    By  ANTHONY,  a  Verified Buyer  from  Port Colborne Ontario Canada  on  November 13, 2024
    I've been using this oil in my 75hp Yamaha for 10 Plus years I'm a charter boat for fishing which means I depend on my motor running at peak performance This motor idles for 2-6 hours per trip. I inspect my spark plugs regularly and have never had an issue with fouling plugs. when i go to full throttle she never lets me down. I change its oil once a year and like what I see.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Great oil -Look up guide sucks
    By  TOM,  a  Verified Buyer  from  WI  on  November 11, 2024
    Great oil as always. However, got a new motor this year and the look up guide sucks. Hasn’t been changed in years. Just refer to your owners manual for correct application.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I trust AMSOIL for everything!
    By  Clyde,  a  Verified Buyer  from  MO  on  May 02, 2024
    Good stuff! Got it in my cars, trucks (diesel & gas), tractors, mowers, saws, skid steer, backhoe, boat, bikes, & bedrooms (squeaky hinges/springs ya know). AMSOIL hasn't let me down in 25 years. Proud, proud, proud!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Suzuki 150hp & Suzuki 9.9hp
    By  Too Tall,  a  Verified Buyer  from  Port Angeles, WA.  on  April 24, 2024
    Been using Amsoil Marine Oil since motors were new, 2009. Have had zero engine problems. Also use lower unit oil, filters and grease. Quality products
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent !
    By  Richard,  a  Verified Buyer  from  CO  on  April 22, 2024
    Two Thumbs Way High !
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Trusted Protection
    By  Mike K,  a  Verified Buyer  from  NJ  on  April 03, 2024
    I have been running Amsoil marine products in my Yamaha SHO outboards since 2014. The motors run great even under the heavy strain of "run and gun" bass fishing. Shifting with the Amsoil lower gear oil is fantastic, no clunking going between forward/reverse and the contamination during yearly changes is minimal.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Outboard
    By  JACK,  a  Verified Buyer  from  Ontario Canada  on  March 30, 2024
    Have used Amsoil in my Honda 225 s since new in 2006..they now have 1000 hours on them..they have never used any oil ..oil after each season looks like it has never been used
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    25 HP Yamaha
    By  PAUL,  a  Verified Buyer  from  Lexington, KY  on  March 24, 2024
    Can’t get better protection.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Poor service
    By  DANIEL,  a  Verified Buyer  from  Sept-iles  on  March 22, 2024
    Very poor service
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good oil but poor service
    By  DANIEL,  a  Verified Buyer  from  Sept-iles  on  March 22, 2024
    I ordered oil and oil filter for my mercury but they didn’t send me the wright filter and they didn’t gave me my money back…very 30058720 poor service
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  • 5 star rating
    Best on the he market
    By  STEPHEN,  a  Verified Buyer  on  February 29, 2024
    This is the best marine oil out there. Tested it in my boat.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 1 star rating
    marine oil
    By  Larry,  a  Verified Buyer  from  MT  on  December 28, 2023
    I will be changing the oil in my boat motor sometime this spring. this will be the second season on the motor. I was advised by the dealership to use Mercury marine oil on the first oil change for brake-in purposes. This will be the first oil change for Amsoil.
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  • 5 star rating
    MARINE ENGINE OIL
    By  EDWARD,  a  Verified Buyer  from  Great Lakes  on  November 22, 2023
    We have been using this oil in our 1991 4.3L engine for over a decade. The engine now has a few thousand hours on it. We use nothing but Amsoil in all our rigs (trucks, sleds, boat motors)
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    idle
    By  Tony,  a  Verified Buyer  from  port colborne  on  November 10, 2023
    75 HP Yamaha.This oil is great as the years have shown me; as this engine idles 3-6 hours without carbon buildup and when i accelerate to top speed (weather permitting) there is no smoke or hesitation When I check the spark plugs they are in excellent condition .
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Only run the best
    By  MIKE,  a  Verified Buyer  from  Midwest  on  November 01, 2023
    Have been using Amzoil for 17 year's have never had an oil related problem. Put marine oil in 300 hp mercury and 15 hp kicker the kicker was noticeable smoother running.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Marine oil
    By  GEORGE,  a  Verified Buyer  on  October 24, 2023
    Great product. Used in a 2004 Seaswirl. No problems.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Yamaha 225 oil for sure
    By  DANIEL,  a  Verified Buyer  from  Michigan   on  October 20, 2023
    This is the only oil for my Yamaha big motor and my kicker. Amsoil is the way for me
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Marine Grade Oil
    By  GIOVANNI,  a  Verified Buyer  from  Hanna  on  October 15, 2023
    Put this oil in my 2003 Suzuki 4 stroke. Got about 80 hours on the oil. Amsoil superior modifiers work as engineered. Allows the filter to remove all impurities. Oil looks like new. I just change oil filter after the first run of the season
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Unexpected Benefits
    By  Jeff,  a  Verified Buyer  from  Wisconsin  on  October 03, 2023
    We have a 23 ft Chapparal with a Chevy 454 and a Mercruiser Bravo3 outdrive. The 454 has 750 hours and runs as smooth as silk. The Amsoil 10W40 Marine is very special. The throttle response is incredible and the consumption of fuel is minimal. Considering this is a Chevy / Mercruiser454 I expected this boat to be a gas guzzler. The Mercruiser 7.4 liter has multi port fuel injection and is far more efficient than the Chevy 350 Mercruiser. Using Amsoil synthetic has made a tremendous difference. We cruise our boat on Lake Geneva in southern Wisconsin, and can circle the 25 to 26 miles around the lake using a little more than 5 gallons of fuel. The previous owner was somewhat cheap and used 10W40 conventional oil. He got about 3 mpg and refused to believe the difference I got using Amsoil. My fuel savings over the course of the Summer paid for the 6 qts of of Amsoil 3 times over using conventional oil. This is a clear cut example of cost versus price. I can actually say that the Amsoil literally paid for itself over lower priced conventional oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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