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Customer Ratings & Reviews

AMSOIL 10W-40 Synthetic Marine Engine Oil

Product code : WCFQT-EA

4.9 star rating Read 82 reviews

Customer Rating

4.9

84% would recommend

  • 5 79
  • 4 1
  • 3 1
  • 2 1
  • 1 0

AMSOIL 10W-40 Synthetic Marine Engine Oil

4.9 star rating Based on 82 reviews
  • 5 star rating
    Outboards
    By  Louie,  a  Verified Buyer  from  Chicago  on  July 06, 2018
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    Oil I could trust running offshore
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Simply the Best
    By  Mismo Titan,  a  Verified Buyer  from  West Palm Beach  on  June 16, 2018
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    We run our sea doos hard and this oil has never let us down. For supercharged skis there are no friction modifiers and it's JASO MA2 which is safe for our superchargers. I've been running amsoil in all my products for a while now and won't run anything else.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Loyal customer
    By  Jeff,  a  Verified Buyer  from  Woolford,MD  on  May 30, 2018
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    Good product, quick delivery, nice website, I'm a fan of Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    4-Stroke Suzuki Outboard
    By  Bobo0415,  a  Verified Buyer  from  SW Florida  on  May 14, 2018
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    Better than Mobile 1. Increased top end, engine runs more smooth at idle. Don't waste your time buying oil from the outboard manufactures, over priced and over rated. Amsoil exceeds Suzuki requirements and will not void warranty. Bought a case, saved on the shipping.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  Showman,  a  Verified Buyer  from  West Michigan  on  April 15, 2018
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    I started using amsoil in my Yamaha because I did not have hour meter to keep track of hours thinking amsoils superior oil would give me some forgiveness if I went a little over recommend hours. I added hour meter, will still use amsoil under preferred customer plan.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I would use nothing else
    By  Trotline,  a  Verified Buyer  from  Petal ms  on  March 05, 2018
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    I use this in my 50hp 4- stroke and you could immediately tell a difference. It ran much smoother and quieter.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Would not put anything else in my yacht.
    By  Mike,  a  Verified Buyer  from  Valpo, In  on  January 21, 2018
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    Great marine oil. Use it in the boat and jetskis.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    works great n my boat
    By  mdd,  a  Verified Buyer  from  granbury Texas  on  January 18, 2018
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    I've added this to my marine inboard motor and seems to be running very well
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product! Highly recommend it...
    By  John,  a  Verified Buyer  from  Springfield, VA  on  January 17, 2018
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    Outstanding product...
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Going to use this for first time with high expectations
    By  Paul - boater,  a  Verified Buyer  from  Woodbridge, VA  on  January 12, 2018
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    Installed in both of my 8.1L Mercruuser engines on my 40' Boat. Also going in my generator. Hope to get the advertized results.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Will continue to use it
    By  John R.,  a  Verified Buyer  from  Toronto, ON,  on  January 12, 2018
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    I have used the 10w40 Marine oil in my Yamaha Waverunner for awhile and to date just great results.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    In all Mercury four strokes
    By  Reg,  a  Verified Buyer  from  St-Zotique  on  December 15, 2017
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    I have ued this in my 115 mercury efi fourstroke and also my 150 efi fourstroke. Now I use it in my Mercury 225 Verado. Best oil to use here in Canada . No more hard starting when the température gets down close to freezing and a great remplacement for Mercury 25-40 semi synthétique oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product
    By  erictm,  a  Verified Buyer  from  Casey,IL  on  December 03, 2017
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    Using it in my third engine with great results. Not a repair one on the first two. Keeps engine very clean.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 3 star rating
    Oil for my PWC
    By  R,  a  Verified Buyer  from  Canada  on  October 20, 2017
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    I like the product, oil seems to be better then YamaLube, Stays clear longer, while YamaLube becomes non transparent and dark grey almost black within 10 hrs. Have AmsOil in high RPM SVHO engine for 35 hrs now and its still clear and light yellow color. However overall purchasing experience was less the pleasant. First, even though the address was correct, they did not ship on time because they could not read the address properly, then the courier didn't know what to do with the package. So because of that it unnecessary took long time to receive the product.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    best of the best!!
    By  matt,  a  Verified Buyer  from  madison wi  on  September 11, 2017
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    having a $15k investment and protecting it starts with Amsoil. I use it in everything I own an have had ZERO problems.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great for Sea-Doo
    By  Dennis,  a  Verified Buyer  from  Lexington, SC  on  September 09, 2017
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    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
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    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
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    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
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    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
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    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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