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Customer Ratings & Reviews

Signature Series Max-Duty Synthetic Diesel Oil 15W-40

Product code : DMEQT-EA

4.9 Read 598 reviews

Customer Rating

4.9

85% would recommend

  • 5 568
  • 4 26
  • 3 1
  • 2 1
  • 1 2

Signature Series Max-Duty Synthetic Diesel Oil 15W-40

4.9 Based on 598 reviews
  • 5
    Best of the best
    By  JOHN,  a  Verified Buyer  from  Long Island NY  on  July 29, 2021

    Describe the issue

    You cannot get better oil.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 4
    Diesel tractor
    By  Richard,  a  Verified Buyer  from  PA  on  July 29, 2021

    Describe the issue

    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.
  • 5
    Great product
    By  LOREN,  a  Verified Buyer  from  Ohio  on  July 27, 2021

    Describe the issue

    Absolutely a great product highly recommended product
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Duramax
    By  REG,  a  Verified Buyer  from  BC  on  July 25, 2021

    Describe the issue

    Extended change intervals and lessens oil consumption
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    The absolute best!
    By  KEVIN,  a  Verified Buyer  from  Newhall, Ca  on  July 24, 2021

    Describe the issue

    2nd to none!
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Great oil
    By  ANDREW,  a  Verified Buyer  on  July 24, 2021

    Describe the issue

    I have a 06 duramax and my truck runs great on Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Great product
    By  JIM,  a  Verified Buyer  from  Jacksonville, Fl  on  July 23, 2021

    Describe the issue

    Great product, no issues.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    The ONLY oil I use!
    By  JUSTIN,  a  Verified Buyer  from  Forney TX  on  July 22, 2021

    Describe the issue

    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.
  • 5
    Reliable and quick delivery
    By  ROBERT,  a  Verified Buyer  from  80134  on  July 12, 2021

    Describe the issue

    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.
  • 5
    Duramax
    By  DENNIS,  a  Verified Buyer  from  Indiana   on  July 11, 2021

    Describe the issue

    Love this for my duramax.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Good quality
    By  RONNIE,  a  Verified Buyer  on  July 10, 2021

    Describe the issue

    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.
  • 5
    Best oil
    By  PIERRE,  a  Verified Buyer  from  Ontario   on  July 07, 2021

    Describe the issue

    Been using this oil for over 30 years.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Diesel oil
    By  JOHN,  a  Verified Buyer  from  Panama City   on  July 06, 2021

    Describe the issue

    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.
  • 5
    Diesel review
    By  ROBBIE,  a  Verified Buyer  on  July 05, 2021

    Describe the issue

    Great service and fast delivery and my truck runs much better on Amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Heavy duty engine oil
    By  OLIVER,  a  Verified Buyer  from  Windsor  on  July 05, 2021

    Describe the issue

    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.
  • 5
    Best of the best
    By  KEVIN,  a  Verified Buyer  from  Grain Valley Mo.  on  July 05, 2021

    Describe the issue

    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.
  • 5
    Signature Series Max-Duty Synthetic Diesel Oil 15W-40
    By  BARRY,  a  Verified Buyer  from  39466  on  July 04, 2021

    Describe the issue

    2015 GMC Denali will always use the highest grade oil I can for this vehicle
  • 5
    Great product
    By  GREGORY,  a  Verified Buyer  on  July 03, 2021

    Describe the issue

    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.
  • 5
    Good quality
    By  HECTOR,  a  Verified Buyer  from  Florida   on  July 03, 2021

    Describe the issue

    I recommend 100%
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Excellent/Best Diesel oil on the Market.
    By  JR,  a  Verified Buyer  from  New Jersey   on  July 03, 2021

    Describe the issue

    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.