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

Product code : DMEQTC-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 15W-40 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,537 reviews
  • 5 star rating
    15W-40 Max Duty
    By  KEITH,  a  Verified Buyer  on  October 29, 2021
    This oil is doing great in my 2000 7.3 Powerstroke, I run a Amsoil bypass filter and the oil analysis says everything looks good. I'm going to stick with it!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  IAN,  a  Verified Buyer  from  VA  on  October 29, 2021
    This product runs oil temps in line with my previous brand(Schaffer’s) but dramatically decreased the number of regens needed. I will keep usong
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Power stroke 7.3
    By  JOHN,  a  Verified Buyer  from  Southern California   on  October 25, 2021
    Great oil, My truck has almost completely stopped using oil, engine runs quieter and smoother. I've tried most brands
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Protect your investment
    By  CHARLES,  a  Verified Buyer  on  October 23, 2021
    Great products,fast delivery. Peace of mind
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    700 hp diesel
    By  WARREN,  a  Verified Buyer  from  New Mexico   on  October 23, 2021
    For the last 50k miles or so this truck has had amsoil and there is a noticeable difference in how the engine sounds at idle. May not make sense but its true. Im not nice to this truck at all and I have comfort knowing that my oil is there for me. When my rods leave the block it won't be from a lack of lubrication
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    great product
    By  PATRICK,  a  Verified Buyer  from  Texas  on  October 21, 2021
    second oil change with Amsoil great product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome costumer service
    By  SHANNON,  a  Verified Buyer  on  October 20, 2021
    LD Synthetics was easy to communicate with and had great advice. Highly recommend
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  MIKE,  a  Verified Buyer  on  October 20, 2021
    Amsoil always arrives in a timely fashion and my engine loves it. Would recommend this oil to anybody who wants the best for their diesel.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil in the market
    By  CHRIS,  a  Verified Buyer  on  October 20, 2021
    I run AMSOIL in my new Cummins and it’s amazing. I had my oil tested by an independent lab and it is better than any other oil on the planet!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil 15w40 diesel oil
    By  RONNALLE,  a  Verified Buyer  from  Parker  on  October 15, 2021
    Up to 25000 miles for next oil change. With amsoil oil filter and product. Recommend oil sample's during long drain interval.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent
    By  MATTHEW,  a  Verified Buyer  from  New Jersey   on  October 13, 2021
    Excellent product, first time running AMS oil I noticed my diesel run smoother immediately.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    oil change
    By  LUIS,  a  Verified Buyer  from  port barrington  on  October 12, 2021
    great oil love it
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Runs like new
    By  SAMUEL,  a  Verified Buyer  from  Nyc  on  October 09, 2021
    Keeps my trailblazer Ss running strong
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome Product
    By  act,  a  Verified Buyer  from  Maplesville  on  October 08, 2021
    I will not use anything else, Works great, Highly Recommend
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  STEVE,  a  Verified Buyer  from  Michigan   on  October 08, 2021
    I love this product has not let me down
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesomeness
    By  ASA,  a  Verified Buyer  on  October 08, 2021
    Always makes my Truck run like new every time I change the oil. That’s not an overstatement either, I’ve used royal purple for years and then I decided to switch over due to all my buddies who I know run Amsoil. Best that money can buy
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product
    By  Ray,  a  Verified Buyer  from  Nebraska   on  October 04, 2021
    Shipping was quick. Great buy. Comparable to what’s at your local stores. I have both engine oil and differential oil in my truck. Love them both.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  MICHAEL,  a  Verified Buyer  from  Winchester Virginia   on  October 04, 2021
    Great oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil, all I use in everything.
    By  MYRON,  a  Verified Buyer  from  Alberta Canada  on  October 04, 2021
    This is great oil, I use Amsoil products in all my vehicles and love it! Wouldn't use anything else.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great
    By  PHILIP,  a  Verified Buyer  on  October 03, 2021
    Will use again
    Bottom Line
    Yes, I would recommend this to a friend.
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