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Customer Ratings & Reviews

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
    Quality Product
    By  CURTIS,  a  Verified Buyer  from  Colorado  on  July 30, 2021
    I believe the test reports I have read on google. Quality product for my vehicles
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best of the best
    By  JOHN,  a  Verified Buyer  from  Long Island NY  on  July 29, 2021
    You cannot get better oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Diesel tractor
    By  Richard,  a  Verified Buyer  from  PA  on  July 29, 2021
    This is only oil I have used in my cub cadet tractor since purchased in 2000.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  LOREN,  a  Verified Buyer  from  Ohio  on  July 27, 2021
    Absolutely a great product highly recommended product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Hasn't let me down
    By  JEFF L,  a  Verified Buyer  from  Pensacola, FL  on  July 26, 2021
    I have been running Amsoil diesel oil in my 5.9 cummins for over 10 years without issue. When I recently had the valves adjusted, the mechanic commented on how clean everything looked under the valve cover and saw no signs of unusual wear. That's the kind of report I love to hear.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Duramax
    By  REG,  a  Verified Buyer  from  BC  on  July 25, 2021
    Extended change intervals and lessens oil consumption
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil and filter
    By  MIKe ,  a  Verified Buyer  on  July 25, 2021
    Great oil been using this since 2007. Along with the oil filter and oil stabilizer.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The absolute best!
    By  KEVIN,  a  Verified Buyer  from  Newhall, Ca  on  July 24, 2021
    2nd to none!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  ANDREW,  a  Verified Buyer  on  July 24, 2021
    I have a 06 duramax and my truck runs great on Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  JIM,  a  Verified Buyer  from  Jacksonville, Fl  on  July 23, 2021
    Great product, no issues.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The ONLY oil I use!
    By  JUSTIN,  a  Verified Buyer  from  Forney TX  on  July 22, 2021
    I have a 2008 LMM and used to use T6 (if you are looking at this oil, you should know what that is) cause my grandfather used it in his diesels. Found this, started using it. Everything noticeably smoother. Quick delivery and got a good discount program. Oh, and I get stickers too. Haha
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Reliable and quick delivery
    By  ROBERT,  a  Verified Buyer  from  80134  on  July 12, 2021
    Been using Amsoil for many years knowing the performance of their many products, I will continue to be a loyal customer.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Duramax
    By  DENNIS,  a  Verified Buyer  from  Indiana   on  July 11, 2021
    Love this for my duramax.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good quality
    By  RONNIE,  a  Verified Buyer  on  July 10, 2021
    I’m Very happy with this product. My truck is happy too 6.7 cummins
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel Oil
    By  MARK A,  a  Verified Buyer  from  Maine  on  July 08, 2021
    Have been using this oil for several years and recently did a CCV service and it was very clean in tray. I would attribute this to the quality of the oil. The soot turns the oil black due to emission systems configuration, but this oil keeps on working.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil
    By  PIERRE,  a  Verified Buyer  from  Ontario   on  July 07, 2021
    Been using this oil for over 30 years.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  JOHN,  a  Verified Buyer  from  Panama City   on  July 06, 2021
    In my opinion this is a good oil to run in a Cummins Diesel engine good cleaning properties
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel review
    By  ROBBIE,  a  Verified Buyer  on  July 05, 2021
    Great service and fast delivery and my truck runs much better on Amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Heavy duty engine oil
    By  OLIVER,  a  Verified Buyer  from  Windsor  on  July 05, 2021
    Best engine oil ever. Keep the motor clean . Clean means also long life for the engine
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best of the best
    By  KEVIN,  a  Verified Buyer  from  Grain Valley Mo.  on  July 05, 2021
    I use all of Amzoil products in every thing I own, I just had the oil changed in my truck by the dealership because I have to do to warranty contract, drove for a week and changed it with my Amzoil, noticeably quieter (Deisel). I paid almost 80 grand for the truck I want the best oil for it.
    Bottom Line
    Yes, I would recommend this to a friend.
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