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Customer Ratings & Reviews

AMSOIL 10W-40 Synthetic Marine Engine Oil

Product code : WCFQT-EA

4.9 star rating Read 87 reviews

Customer Rating

4.9

85% would recommend

  • 5 84
  • 4 1
  • 3 1
  • 2 1
  • 1 0

AMSOIL 10W-40 Synthetic Marine Engine Oil

4.9 star rating Based on 87 reviews
  • 5 star rating
    Great for Sea-Doo
    By  Dennis,  a  Verified Buyer  from  Lexington, SC  on  September 09, 2017
    Works great in my supercharged Sea-Doo. No issues with supercharger slipping, motor runs very smoothly. Will continue to use this.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The best their is
    By  Crusiers inc,  a  Verified Buyer  from  Illinois  on  August 06, 2017
    I use this oil in my 7.4 liter mercrusier motor. Now Amsoil and Mercrusier recommended that I use the 20w 40 synthetic blend. But I wanted full synthetic. This oil is AWESOME!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Will buy this product again
    By  tootall,  a  Verified Buyer  from  Port Angeles, WA  on  July 26, 2017
    Use in my 150HP and 9.9HP Suzuki Outboards
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  • 5 star rating
    Multiple motors
    By  MrEd,  a  Verified Buyer  from  Rocky Point, NC  on  June 26, 2017
    I use Amsoil in my: 2008 M-Benz V-6 diesel (meets the 229.51 spec.); 2017 Subaru 2.5 normally aspirated 4 cylinder boxer (0W-20 Signature Series); 2013 Yamaha 90 hp outboard; 1999 Honda V-2 10kw generator; pressure washer, and lawn mower. I change oil in all these motors once a year, along with an Amsoil filter for the Forester. I switched from M____ products to Amsoil after I personally compared the specs for 5 quality motor oils, including the "Subaru" oil (actually Idemitsu Oil) and found that Amsoil matched or was better in most of the parameters on all the oils, particularly the NOACK value (for volatility or "boiling off".) I was especially interested in the 0W-20 values, since I had a chance to choose a specific oil to use in the new Forester for its life. I found that there was a huge NOACK difference between Amsoil and the Subaru/Idemitsu oil. No doubt that is why Subaru recommends a 6,000 oil change interval, and Amsoil Signature Series is at 25,000 miles. None of the other oils matched Amsoil's NOACK value. That comparison convinced me. At 500 miles I drained the Subaru/Idemitsu oil and switched to Amsoil Signature Series, and changed it again at 6,000 miles and am now on a yearly change cycle, since I average between 10,000 and 13,000 miles a year. Cheaper and better - a no brainer.
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  • 5 star rating
    The best engine oil
    By  Don the Biker,  a  Verified Buyer  from  Topeka, KS  on  May 21, 2017
    AMSOIL is the only engine oil I will use in my vehicles, motorcycle, and outboard motor. It improves the gas mileage on my Victory motorcycle by over 10% compared to OEM synthetic oil. That convinces me that there synthetic oil reduces engine friction and should help the engine last longer.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I will always use this product. Very satisfied.
    By  James,  a  Verified Buyer  on  December 25, 2016
    I use this product in a 2013 mercury 150hp 4 stroke outboard. It runs great with no issues. Living in the northeast our season is short so I can only get about 75 hrs of use. My only issue is that you do not make an oil filter for this engine.
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  • 5 star rating
    I run only Amsoil
    By  Brian,  a  Verified Buyer  on  December 08, 2016
    Have this in my new Waverunners after break in for winter storage.
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