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

Product code : DMEQT-EA

4.9 star rating Read 1,543 reviews

Customer Rating

4.9

92% would recommend

  • 5 1478
  • 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 1,543 reviews
  • 5 star rating
    This oil is my oil for My Ram 6.7 liter Cummins
    By  STAN,  a  Verified Buyer  from  Spring Texas  on  April 29, 2023
    I usually change oil every 10K but if it goes over that I am not worried. Amsoil will continue to provide protection.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Always my first choice
    By  Bryan,  a  Verified Buyer  from  TX  on  April 28, 2023
    I always use Amsoil when I am traveling and pulling my RV. It gives me peace of mind knowing I use the best.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil for my Cummins diesel
    By  TIMOTHY,  a  Verified Buyer  from  Northern California   on  April 23, 2023
    I have used this oil in my 1997 Ram 12 valve diesel for many years. I tried other brands designed for diesel engines but none perform as well as AMSOIL. I have less oil consumption and believe it or not, my oil stays cleaner over the life of the oil change interval. Well worth the extra cost.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil.
    By  ROBERT,  a  Verified Buyer  on  April 18, 2023
    Motor runs quieter and smoother.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Love the 2.5 gal jug
    By  DEAN,  a  Verified Buyer  from  Clinton Washington  on  April 17, 2023
    The 2.5 gal jug makes an oil change super easy.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Ambulance Oil
    By  BARRY,  a  Verified Buyer  from  CCMICU  on  April 17, 2023
    Excellent oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel Longevity
    By  GryGuy,  a  Verified Buyer  from  Kentucky  on  April 17, 2023
    I did a test on my 2009 Cummins - I ran this oil with the Ea0 filter and tested it at a third party lab every 6,000 miles. Every test came back perfect until 24,000 mile interval - at this point, the test showed “slightly elevated” Molybdenum levels. The Certificate of Analysis for this specific test noted that the oil was still perfectly safe to run despite the slightly elevated Molybdenum. To summarize, this oil saves me money on oil changes and protects my diesel engine like no other on the market. Thank you and I love you AMSOIL!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    the best
    By  WILLIAM,  a  Verified Buyer  from  Jacksboro tn  on  April 17, 2023
    I've known amsoil since the 70's, I trusted it then and I trust it now.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Valuable
    By  DAN,  a  Verified Buyer  from  Iowa  on  April 16, 2023
    This stays clean looking a lot longer than anything else I've used. And for hotshot runs cross country it's a must for fuel economy
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I only use Amsoil
    By  James,  a  Verified Buyer  from  TX  on  April 11, 2023
    I use Amsoil in all my vehicles including motorcycles.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  STANLEY,  a  Verified Buyer  from  Thornton  on  April 07, 2023
    Only oil I use for my F250.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Love that oil
    By  EDWARD,  a  Verified Buyer  from  Morro bay ca  on  April 05, 2023
    Have a 2009 duramax 364,000 miles runs like a champ. Would not use any other oil in it.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Cummins
    By  BARRY,  a  Verified Buyer  from  Statesville NC  on  April 04, 2023
    Have a 2001, dodge ram 2500 with a Cummins diesel and automatic transmission. I’ve been using this oil since I bought the truck in 2004 and have had zero oil related issues, and this truck is regularly, overloaded and overworked.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil!
    By  RICK,  a  Verified Buyer  from  New Jersey   on  April 04, 2023
    Amsoil is the best oil on market! Have had it tested after using and viscosity stands true! Only oil I use in all my motors and engines
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amazing oil
    By  MATTHEW,  a  Verified Buyer  on  April 02, 2023
    This oil out performs the Ram suggested oil for the ecodiesel and the 2.5 gallon jug is the perfect size. Couple the oil with wax filter and it is a winning combination.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  BENJAMIN,  a  Verified Buyer  from  Farwell, MI   on  April 02, 2023
    Great product been using amsoil for years now.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent Amsoil Product
    By  JASON,  a  Verified Buyer  from  Spruce Grove   on  March 30, 2023
    I've run this oil and Royal Purple synthetic 15w40. I do find Amsoil quietens my older deisel down better.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The best
    By  MARK,  a  Verified Buyer  on  March 25, 2023
    I have been running this oil since I bought the truck new. I only trust Amsoil in my truck.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Used in my 97 Ford F-350 power stroke
    By  Bushwacker,  a  Verified Buyer  from  MI  on  March 23, 2023
    Seems to be a great product. I'm only driving the truck about 8000 miles a year. So, I change the filter and add 2 quarts at 6 months, 1 complete change 1× a year. I haul a heavy pick-up camper, and prior a 30 ft 5th wheel. The engine is running great at 215,000 miles
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil 15w-40
    By  ANDREW,  a  Verified Buyer  on  March 22, 2023
    Been using Amsoil’s 15w-40 on my Duramax for years and I absolutely love it. I can get 15-18k intervals out of it and it’s still got a couple thousand more miles left in it. Take care of your vehicle and it’ll take care of you… run amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
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