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AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

Product code : DMEQT-EA

4.9 star rating Read 1,550 reviews

Customer Rating

4.9

92% would recommend

  • 5 1485
  • 4 45
  • 3 9
  • 2 3
  • 1 8

AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,550 reviews
  • 5 star rating
    Great
    By  Chery,  a  Verified Buyer  from  Lompoc   on  September 20, 2020
    Great price
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Diesel oil available!
    By  Baldeagle535,  a  Verified Buyer  from  New Mexico  on  September 20, 2020
    This product performs as advertised and tested. The engine starts easily in cold weather; it runs cool in hot weather. It protects the engine against excessive wear. I am a happy customer after using it in two different diesel engines.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  September 17, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Product Review
    By  Eastern Light Fisheries. ,  a  Verified Buyer  from  Montauk, N.Y.  on  September 17, 2020
    Best diesel oil on the market...!!!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  JBC,  a  Verified Buyer  from  La.   on  September 16, 2020
    Very good oil 15W40 SS Diesel oil is all i run in my duramax trucks.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    2003 Dodge Ram 3500
    By  Gimpy ,  a  Verified Buyer  from  Washington State   on  September 16, 2020
    Amsoil is the only brand I run in my vehicles and with extended drain intervals and proven results it’s a no brainer.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  September 16, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Synthetic 15W40
    By  Anonymous,  a  Verified Buyer  from  Greentown,Indiana  on  September 16, 2020
    I love this oil. Have been using it for a long time. I have a 2005 Dodge 3500. My mileage went up to 23+ miles per gallon. Up 3 MPG. I don't drive as much since retired, so I change oil once a year. This is excellent oil for any diesel.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  September 16, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  September 16, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Badass oil company
    By  Anonymous,  a  Verified Buyer  from  Ruston, LA  on  September 16, 2020
    Great product and great company to deal with. I enrolled in the preferred customer program and it is great. Fantastic catalog and orders were shipped immediately.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome oil
    By  5.9 Cummins,  a  Verified Buyer  from  Western Oklahoma  on  September 16, 2020
    I switched to this oil in my 2006 dodge Cummins. 1st start up with the Amsoil my engine sound quieter and felt smoother. Best oil I’ve used.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  September 16, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil
    By  Loren,  a  Verified Buyer  from  Mount pocono  on  September 16, 2020
    Great product from amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Motor oil
    By  Codymc,  a  Verified Buyer  from  Oakley, CALIFORNIA   on  September 16, 2020
    Worked well in my truck.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I would recommend it
    By  Tim,  a  Verified Buyer  on  October 27, 2019
    Using in 2019 L5P so good so far??
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  • 5 star rating
    Great Diesel Oil
    By  Curtis,  a  Verified Buyer  on  October 25, 2019
    This oil is the finest quality I have ever run into. That is why it is in all our Diesel trucks.
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  • 5 star rating
    Best oil for emission sensitive vehicles
    By  Richard,  a  Verified Buyer  on  October 23, 2019
    Use on my stock 2012 duramax with over 100,000 miles. No issues with dpf or other emission systems. With oil analysis, it holds up great for around 15,000 miles.
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  • 5 star rating
    Looks like a good thing
    By  Joseph,  a  Verified Buyer  on  October 22, 2019
    Time will tell. Engine temperature down by 25 to 30 degrees
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  • 5 star rating
    Definitely recommend Amsoil over any other brand
    By  Michael,  a  Verified Buyer  on  October 11, 2019
    I travel a lot fishing bass tournaments all over the country pulling a 21 foot bass boat and I immediately noticed a difference when I started using Amsoil in my Ram 2500 diesel. Engine runs quieter and smoother. Can't say enough good things about Amsoil products.
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