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Customer Ratings & Reviews

SAE 15W-40 Heavy-Duty Diesel and Marine Oil

Product code : AMEQT-EA

4.9 star rating Read 239 reviews

Customer Rating

4.9

81% would recommend

  • 5 227
  • 4 10
  • 3 2
  • 2 0
  • 1 0

SAE 15W-40 Heavy-Duty Diesel and Marine Oil

4.9 star rating Based on 239 reviews
  • 5 star rating
    the only oil for my boat
    By  JOHN,  a  Verified Buyer  from  sunshine coast, BC  on  May 15, 2022
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    just had the valve cover off my Cummins Marine 5.9. pristine at 1000 hours. Amsoil products are the only oils in all my power equipment.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    1977 Ford 1600 tractor
    By  PAUL,  a  Verified Buyer  from  clinton, oh  on  April 25, 2022
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    So far so good Time will tell
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil for my 2006 DMAX LBZ
    By  RUSS,  a  Verified Buyer  from  South Louisiana   on  April 18, 2022
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    Been using this oil since first oil change.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    BEST OIL FOR MY CUMMINS 8.9 DIESEL PUSHER EVER
    By  DAREDEVILLEGEND,  a  Verified Buyer  from  TAMPA BAY AREA, FLORIDA  on  April 17, 2022
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    The AMSOIL for my diesel is AMAZING. I would never use anything else. Thank You for such a GREAT Product :-) God Bless Bob
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel engine oil
    By  R.G.,  a  Verified Buyer  on  March 20, 2022
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    Love many different Amsoil products. Diesel engine oil works great in my Tractor
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    A Great Synthetic Oil
    By  SHERMAN,  a  Verified Buyer  on  February 16, 2022
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    I've been using Amsoil Synthetic Oil for many years and my diesel engines just keeps lasting.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Oil
    By  GEORGE,  a  Verified Buyer  from  NC  on  January 06, 2022
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    AMSOIL products are always reliable and ship quickly. Packaging is durable and clean. They've even sent me free bottles of firearm cleaner in which worked so well I purchased them on top of my usual oil orders.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesels' best friend
    By  Kent,  a  Verified Buyer  from  OR  on  December 24, 2021
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    Always use this in every diesel rig. Some now as old as 25 yrs. Never an oil problem. On the road at all times and never down due to oil. Don't use this at your own peril. Peace of mind is crucial.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  KENNETH,  a  Verified Buyer  from  Maryville tn.  on  November 06, 2021
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    Love this product great price to. Going to switch all my vehicles over to amzoil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  Rod,  a  Verified Buyer  from  MI - Michigan  on  November 01, 2021
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    Fast shipping high quality product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great high quality product
    By  Rod,  a  Verified Buyer  from  MI  on  October 19, 2021
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    Fast shipping great quality!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome
    By  MATTHEW,  a  Verified Buyer  on  October 17, 2021
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    Fast shipping great product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    15w-40 Diesel/Marine OIl
    By  BEN,  a  Verified Buyer  from  Tulsa  on  September 16, 2021
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    I have used this oil for many, many years in my 1985 Mercedes Benz 300SD Turbo Diesel and my 1951 John Deere Model R diesel tractor engine with excellent results. Zero failures
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Series 3000 - 5w-30
    By  BEN,  a  Verified Buyer  from  Tulsa  on  September 16, 2021
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    This is the best oil for my 2004 John Deere X495 diesel tractor, the pony motor on my 1951 John Deere Model R diesel tractor and all my smaller 4 cycle gasoline engines. Been using it in these applications for years and years with excellent results and zero engine failures.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 3 star rating
    Oil life
    By  ROBERT,  a  Verified Buyer  from  Edgewater,(Maryland)   on  September 13, 2021
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    This oil seems to break down at approximately 125 hours. The oil turned black and got really thin. This caused my oil pressure to drop 7-10 lbs. I’m going to give it one more try before I witch brands. This oil is being used in a Cummins 5.9QSB that is in my boat and they recommend 250 hour oil changes. This oil will never make it that long. Thank you for your time.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The only oil i will use in my truck
    By  SCOTT,  a  Verified Buyer  from  Houston  on  September 05, 2021
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    I have used amsoil in my 5.9 cummins for 11 years now. 230k miles and performs like it is new.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    GMC Duramax 6.5 LBZ (2007)
    By  TED,  a  Verified Buyer  from  Colorado   on  August 25, 2021
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    Run this in my 2007 pre-DEF engine since new. First ran for 15K and then tested results with SOAP analysis—results were excellent. Now run the oil at least 30K miles, changing filters every 15K. Good MPG and cold wx starts to 0 degrees F. Highly recommend for towing and tough engine use conditions.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great diesel oil for pre-dpf engines
    By  ALEK J,  a  Verified Buyer  from  NC  on  July 30, 2021
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    I've been using this oil nearly exclusively for the past 15 years in my 2006 Duramax. I average 35,000 miles between oil changes and monitor every 10-12k miles when I change the filters. Amsoil has always provided great protection for my engine. The high TBN lets me use the oil longer than any conventional oil and my truck is running great with 256,000+ miles. Great oil, I'll continue to use it.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    20+ Years
    By  KIT,  a  Verified Buyer  from  Marysville, WA  on  July 30, 2021
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    This is all I have used in my 97 Ford F-350 Powerstroke. Formulated especially for these motors.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Going for 50,000 mi
    By  ALEK J,  a  Verified Buyer  from  NC  on  July 11, 2021
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    I’ve been using this oil for 15 years with excellent results. High TBN promotes its use for extended oil change intervals. I’ve run several 40,000 mi intervals. Just added the PPE oil pan and filter adding an extra 2qt capacity to the engine, and draining 99% of the old oil. Hoping to get 50,000 mi on this oil!
    Bottom Line
    Yes, I would recommend this to a friend.
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