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AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil

Product code : DEOQTC-EA

4.9 star rating Read 1,537 reviews

Customer Rating

4.9

92% would recommend

  • 5 1472
  • 4 45
  • 3 9
  • 2 3
  • 1 8

AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,537 reviews
  • 5 star rating
    Signature Series Max-Duty Synthetic Diesel Oil 15W-40
    By  BARRY,  a  Verified Buyer  from  39466  on  July 04, 2021
    2015 GMC Denali will always use the highest grade oil I can for this vehicle
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  • 5 star rating
    Great product
    By  GREGORY,  a  Verified Buyer  on  July 03, 2021
    Started using this in my 2004 ram 2500 Cummins and is doing a great job protecting the internal parts of the engine
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good quality
    By  HECTOR,  a  Verified Buyer  from  Florida   on  July 03, 2021
    I recommend 100%
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent/Best Diesel oil on the Market.
    By  JR,  a  Verified Buyer  from  New Jersey   on  July 03, 2021
    Signature Series Max Duty Diesel is absolutely the best oil on the Market. After several years of use I have no problems with my fleet and save $ with longer drain intervals.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Perfect for hard driving
    By  GRANT,  a  Verified Buyer  from  Southern California  on  July 02, 2021
    I use my truck for light duty work, but alot of extreme driving conditions like traffic can wear your engine out. Ive put this in my truck and my dad’s truck for thousands of miles and my engine always runs perfect. Never skip on quality when it comes to taking care of your baby
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Diesel Oil Available
    By  KLINT,  a  Verified Buyer  from  Kentucky  on  June 27, 2021
    My truck loves this oil and so do I.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The Best oil
    By  DAVID,  a  Verified Buyer  from  Berryville   on  June 26, 2021
    We have used other oils in our diesel gator 6x4 but none matches the quality of Amsoil. When we switched to Amsoil diesel 5w40 the gator runs a lot my smoothly.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Graeat Product
    By  IMAD,  a  Verified Buyer  from  Kent WA  on  June 23, 2021
    Excellent product, I love Amsoil, use it on my Diesel Truck, great engine protection
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil 👍
    By  LANCE,  a  Verified Buyer  on  June 21, 2021
    Nothing but amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  JORGE,  a  Verified Buyer  on  June 20, 2021
    Always on time shipping is great awesome products!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The engine works and running really smooth
    By  LUIS,  a  Verified Buyer  from  Homestead   on  June 19, 2021
    I really love how my Duramax engine work with the amsoil signature full synthetic diesel oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    This is the only product I will run in my truck
    By  SEAN,  a  Verified Buyer  from  In exercise owner  on  June 17, 2021
    Gray products have no problems
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good product great packaging.
    By  BRUCE,  a  Verified Buyer  on  June 16, 2021
    All AMS are quality products.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 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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