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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
    Good Oil
    By  CLINT,  a  Verified Buyer  from  Tennessee   on  June 11, 2023
    I have a 2016 Silverado 2500hd LML. When I purchased the truck it had 120,000 miles on it. I have used this product since the first full service that I did on the truck. I change the oil every 5000 miles it runs quit and smooth. Although it is pricey I will remain using it
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Consent product
    By  NATHAN,  a  Verified Buyer  on  June 07, 2023
    Very consent product. I know when a purchase this oil I'm getting a great product every time.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Million mile oil
    By  CHARLES,  a  Verified Buyer  from  Southern California  on  June 04, 2023
    Quality product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best you can get.
    By  RAYBURN,  a  Verified Buyer  from  Virginia   on  June 01, 2023
    Everything runs better with Amsoil oil. I use this in my Duramax.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  RON,  a  Verified Buyer  from  Cottonwood   on  June 01, 2023
    Bought a new 2022 ram 2500 diesel. After a thousand mile break in I changed the oil too amsoil full synthetic six-time protection. I pull a trailer so I want the highest protection I can get in our very hot Redding weather. I will continue to use this oil in my ram!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil, long drain
    By  MICHAEL,  a  Verified Buyer  on  May 30, 2023
    I have used these oil products in my last 3 diesel trucks which don't get a ton of annual miles but I always use the best quality oil with long drain intervals which makes it nice.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil ever!
    By  BRIAN,  a  Verified Buyer  from  Mobile AL  on  May 28, 2023
    Every 10,000 miles at the time I change my oil, doesn’t seem to be using as much as the factory oil usage. So that’s definitely a plus! Will continue to buy AMSOIL!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome oil
    By  Adam,  a  Verified Buyer  from  TX  on  May 22, 2023
    I have had great luck with amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Testing this upgraded formula
    By  KIT,  a  Verified Buyer  from  Washington   on  May 21, 2023
    I’ve used the standard/basic 15w-40 HD synthetic in my 97OBS for decades. With new injectors/hpop/ipr/turbo and inter cooler along with Marty’s e-fuel system I wanted added protection and extended service intervals.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product
    By  MICHAEL,  a  Verified Buyer  from  Valley Springs, CA  on  May 20, 2023
    I have three diesel pick ups and I use this oil in all of them. Great oil and I love the longer intervals between oil changes!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil turbo diesel oil
    By  CODY,  a  Verified Buyer  from  Lake Tahoe. NV  on  May 19, 2023
    I have ALWAYS been and always will be a firm believer that Amsoil is the best there is. I run Amsoil in both my trucks and my SxS.
    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  Pennsylvania  on  May 11, 2023
    Great oil, easy starts in cold weather. Keeps engine clean.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome
    By  CHADWICK,  a  Verified Buyer  from  Sexsmith Alberta  on  May 11, 2023
    Amsoil makes a great product ,I have used this for all of the life of my LMM diesel and it is at approximately 330000 km's. I would recommend their products on any gas or diesel. Here's to the next 330000. 😊
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome product and keeps the Duramax hummin along
    By  RYAN,  a  Verified Buyer  from  West Virginia   on  May 01, 2023
    Awesome product and was shipped in a very timely manner .. will use this product for the life of the truck..21 Chevy 2500 Duramax
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    This oil is my oil for My Ram 6.7 liter Cummins
    By  STAN,  a  Verified Buyer  from  Spring Texas  on  April 29, 2023
    I usually change oil every 10K but if it goes over that I am not worried. Amsoil will continue to provide protection.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Always my first choice
    By  Bryan,  a  Verified Buyer  from  TX  on  April 28, 2023
    I always use Amsoil when I am traveling and pulling my RV. It gives me peace of mind knowing I use the best.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil for my Cummins diesel
    By  TIMOTHY,  a  Verified Buyer  from  Northern California   on  April 23, 2023
    I have used this oil in my 1997 Ram 12 valve diesel for many years. I tried other brands designed for diesel engines but none perform as well as AMSOIL. I have less oil consumption and believe it or not, my oil stays cleaner over the life of the oil change interval. Well worth the extra cost.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil.
    By  ROBERT,  a  Verified Buyer  on  April 18, 2023
    Motor runs quieter and smoother.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Love the 2.5 gal jug
    By  DEAN,  a  Verified Buyer  from  Clinton Washington  on  April 17, 2023
    The 2.5 gal jug makes an oil change super easy.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Ambulance Oil
    By  BARRY,  a  Verified Buyer  from  CCMICU  on  April 17, 2023
    Excellent oil
    Bottom Line
    Yes, I would recommend this to a friend.
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