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

Product code : DMEQT-EA

4.9 star rating Read 1,541 reviews

Customer Rating

4.9

92% would recommend

  • 5 1476
  • 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 1,541 reviews
  • 5 star rating
    Feel the difference
    By  SHAWN,  a  Verified Buyer  from  Wasaga beach   on  October 19, 2025
    Runs better than shell rotella
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Oil For My 6.0 Powerstroke
    By  DYLAN,  a  Verified Buyer  from  New York  on  October 18, 2025
    This is the only motor oil I run in my 2007 6.0 Powerstroke; it runs amazing on it. Injectors fire beautifully, as they're run off high pressure oil in this motor. I know that I am putting the best quality oil in my truck when I use this product. I know many other people with the same generation of truck as mine, they're all running AMSOIL as well. Highly recommend.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    No issues
    By  PennaDiesel ,  a  Verified Buyer  from  Pa  on  October 18, 2025
    I have used Amsoil for years and continue with my newer Cummins with roller lifters, 30,000 miles and no issues.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel products
    By  RadicalD,  a  Verified Buyer  from  Florida  on  October 18, 2025
    Highly recommend all of their diesel products! My Titan loves when these fluids are in her!!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I love this product
    By  VIKTOR,  a  Verified Buyer  from  East Washington  on  October 14, 2025
    Nice oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Satisfied Customer
    By  KENNETH,  a  Verified Buyer  from  Georgia  on  October 14, 2025
    I use this product in my 2024 GMC 2500 duramax diesel. Great results, Great service. I have used this product in my 2013 duramax with the same results. Very satisfied.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Keeps my Duramax running strong!
    By  TALINNA,  a  Verified Buyer  from  Arizona  on  October 13, 2025
    I love this product! It keeps my Duramax running strong and it's absolutely doing its job. Keeps it smooth and at top performance.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    great wear 247k miles later
    By  CRESSMAN,  a  Verified Buyer  from  Maine  on  October 13, 2025
    my truck used to be a fleet truck at where i work. truck has used amsoil since new changed every 25k miles. engine has 0 blow by at almost 250k. The results speak for themselves! i now run amsoil in everything i own.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  KEVIN,  a  Verified Buyer  from  South Carolina   on  October 10, 2025
    Can not say enough about this product and Amsoil. I am a little bias but swear by everything Amsoil. Always keeping my diesel properly lubricated all through the 10k oil changes.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil
    By  LUIS,  a  Verified Buyer  from  Texas  on  October 09, 2025
    excellent product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  RUSS,  a  Verified Buyer  from  Minnesota  on  October 07, 2025
    I will only use the signature series oil in my super duty. I’ve been using it for years now. Absolutely love it!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil kit
    By  RORY,  a  Verified Buyer  from  Nevada  on  October 07, 2025
    Excellent Service. Quick delivery on a great product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  WAYNE,  a  Verified Buyer  from  Idaho  on  October 06, 2025
    It has improved my oil pressure an reduce my engine noise
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great
    By  GAVIN,  a  Verified Buyer  on  October 05, 2025
    As advertised
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good stuff
    By  SCOTT,  a  Verified Buyer  on  October 04, 2025
    Good stuff. 180k on 6.7. No issues I like the 2.5 gallon jugs
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    DIESEL OIL
    By  RONALD,  a  Verified Buyer  from  PHIPPSBURG COLORADO  on  October 02, 2025
    I HAVE USED AMSOIL SINCE 1980, I HAVE USED THIS OIL SINCE 2008 IN THIS DIESEL. I WOULD NOT USE ANYTHING ELSE.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel Oil
    By  JAMES,  a  Verified Buyer  from  Texas  on  October 01, 2025
    Best oil on earth.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Engine Protection
    By  DANIEL,  a  Verified Buyer  from  Alva Wyoming   on  September 26, 2025
    I’ve always been a “Royal Purple” guy, it’s a top of the line product as is their other products- BUT after running Amsoil 15W40 in my 2013 HD Silverado Duramax, it’s “Light Years”better for my MPG, engine oil temperature and power.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Diesel Oil
    By  Dick,  a  Verified Buyer  from  Casco Maine  on  September 21, 2025
    I've been using Amsoil diesel oil for 14 years and my engine runs great.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Diesel oil
    By  JEFFREY,  a  Verified Buyer  on  September 21, 2025
    Great oil. Even put in my diesel tractor. Turbo spools a lot faster.
    Bottom Line
    Yes, I would recommend this to a friend.
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