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

Product code : DMEQT-EA

4.9 star rating Read 1,544 reviews

Customer Rating

4.9

92% would recommend

  • 5 1479
  • 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 1,544 reviews
  • 5 star rating
    Massey running smoothly!
    By  East tenn,  a  Verified Buyer  from  Tennessee  on  June 12, 2021
    Massey sub compact running great! Expect a long life!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Syn Oil
    By  RONALD,  a  Verified Buyer  from  Oregon  on  June 12, 2021
    Been using for years and this is the best
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Really good, I’m happy how the engine is working now
    By  LUIS,  a  Verified Buyer  from  Homestead FL  on  June 11, 2021
    I’m happy to use amsoil synthetic oil for my pickup truck,the engine sounds a lat better than before
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome Stuff
    By  JASON,  a  Verified Buyer  from  Texas  on  June 10, 2021
    Product is the bomb!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil!
    By  RANDAL,  a  Verified Buyer  on  June 09, 2021
    This oil is impressive!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good stuff!
    By  NEHEMIAH,  a  Verified Buyer  from  Indiana   on  June 08, 2021
    Great product and even better customer service and shipping. All my vehicles get Amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature series
    By  COLIN,  a  Verified Buyer  on  June 07, 2021
    Used this product for the last 5 oil changes and many more to come.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product
    By  MICHAEL,  a  Verified Buyer  from  Farmington, CA  on  June 06, 2021
    I love Amsoil products. It gives me great comfort and piece of mind knowing all of my engines from my Can Am side by side, my lawn mowers, motorcycle and all my trucks are protected with the best oils on the market today.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Duramax
    By  Anthony,  a  Verified Buyer  from  MN  on  June 04, 2021
    Great oil for any truck
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    An outstanding CK4 oil
    By  ofelas,  a  Verified Buyer  on  June 04, 2021
    Amsoil's excellent SS oils are the only CK4 lubes I'll use on a CI4+ application, especially if I don't have immediate access to AME/HDD.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great products.
    By  SCOTT,  a  Verified Buyer  on  May 29, 2021
    I have been using 15w40 marine/heavy duty for 25 years. Will be using this new signature series in my 2015 Duramax next oil change (waited 25000miles).
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Longer oil change intervals
    By  BRIAN,  a  Verified Buyer  on  May 29, 2021
    This oil has allowed me to go twice as long between oil changes.(from 7500) to 12-14K. Not having to add any along the way.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    A++++++
    By  JASON,  a  Verified Buyer  from  Lompoc   on  May 29, 2021
    Excellent product highly recommended
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent resilience to heat and cold
    By  DAN,  a  Verified Buyer  from  Iowa  on  May 29, 2021
    Excellent resilience to heat and cold with the quality to go way past any other oils life
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil Ram 3500
    By  MARK,  a  Verified Buyer  from  Texas  on  May 25, 2021
    I like this product so much that I have the next to oil changes ready and waiting. My truck will only be using amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  BRIAN,  a  Verified Buyer  from  Alberta  on  May 24, 2021
    I have had no problems with this oil works well in my truck
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Diesel Oil
    By  PETER,  a  Verified Buyer  from  Vermont  on  May 23, 2021
    I've used Amsoil oil in my diesel engines for years, and their latest oil is the best. Great performance whether it is cold winters or hot summers. I've gone to the same oil for my diesel tractors - and Amsoil keeps them humming. While different viscosities and grades, I have found the extended Euro oils perfect for my diesel turbocharged cars too!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    MegaCab
    By  RICH,  a  Verified Buyer  from  Mesa, AZ  on  May 21, 2021
    My Cummins engine has runs smoother and better with Amsoil. I switched from Rotella which is a great oil but, hands down Amsoil is the best !
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Duramax Diesel oil
    By  WAYNE,  a  Verified Buyer  from  Tennessee   on  May 21, 2021
    I started using Amsoil signature-series-max-duty-synthetic-diesel-oil-15w-40 in my 2009 gmc duramax diesel when I bought it new on the first oil change and every oil change since. My truck has almost 200,000 miles on it. Still runs strong and uses no oil between oil changes. Won’t use any oil but this Amsoil oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Recommend
    By  STEVEN,  a  Verified Buyer  on  May 21, 2021
    I would highly recommend this product
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?

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