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

Product code : DEOQT-EA

4.9 star rating Read 1,551 reviews

Customer Rating

4.9

92% would recommend

  • 5 1486
  • 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 1,551 reviews
  • 4 star rating
    Transport Driver
    By  JEREMY,  a  Verified Buyer  from  TN  on  September 19, 2021
    I have been using Amsoil for years now and currently have close to 350k miles on my Ram 3500 without any engine issues. I would recommend this oil if you want an oil that can withstand the extra temperature and stress put on an engine running 11-12 hrs. a day 2-3 weeks a month.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excelente quality the best oil for my Duramax
    By  LUIS,  a  Verified Buyer  from  Homestead   on  September 19, 2021
    I really love the oil quality , the Duramax engine work amazing
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature Series 5w-40 Diesel OIl
    By  BEN,  a  Verified Buyer  from  Tulsa  on  September 16, 2021
    Been using this oil in my 2019 Ford F350 Super Duty Lariat with the 6.7L Powerstroke Diesel engine and so far so good. Engine runs clean and smooth with zero issues. This is really good oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    AMSOIL DIESEL OIL
    By  ROBERT,  a  Verified Buyer  from  GEORGIA  on  September 15, 2021
    Pulling a 15k # boat, you want to have the best protection you can give your engine! This is the best you can get!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product
    By  CHRISTOPHER,  a  Verified Buyer  from  Missouri  on  September 15, 2021
    I run my duramax quite hard and have for many years. This oil in my mind is the best. I’ve had no issues internally and even more surprising I have noticed the oil to be less dark on change intervals than other brands which is incredible for a diesel in and of itself.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Duramax
    By  DARYL,  a  Verified Buyer  on  September 13, 2021
    Excellent
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 2 star rating
    MAX -DUTY
    By  JACK,  a  Verified Buyer  from  PEORIA IL  on  September 07, 2021
    OIL SEEM TO BE WORKING FINE ONLY BEEN IN THE TRUCK FOR 200 MILES
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  • 5 star rating
    Outstanding!
    By  RICHARD,  a  Verified Buyer  on  September 07, 2021
    Highly recommend!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel Oil
    By  DAVID,  a  Verified Buyer  on  September 07, 2021
    Best oil out there, especially for extreme conditions
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 2 star rating
    Good oil
    By  WAYNE,  a  Verified Buyer  from  Chilliwack   on  September 06, 2021
    It’s great oil. Just did my last oil change and I think it will be the last. As it is already expensive and they increase the price , and made me pay for shipping. That was the last purchase.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Diesel oil
    By  Beardedcajun,  a  Verified Buyer  from  Texas  on  September 05, 2021
    I love the Diesel oil, as I love Amsoil period, very high quality oil, I use their oils in all my trucks, tractors, zero turn, and side x side.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    oil review
    By  CHARLES,  a  Verified Buyer  on  September 05, 2021
    great oil
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  • 4 star rating
    In older Cummins
    By  SHANE,  a  Verified Buyer  on  September 05, 2021
    Have been using this signature series for a great number years in a 2004.5 Cummins haven’t had any issues
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    oil review
    By  CHARLES,  a  Verified Buyer  on  September 05, 2021
    great oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    ecodiesel
    By  Tony,  a  Verified Buyer  from  port colborne Ontario Canada  on  September 05, 2021
    I believe this oil has kept my engine from have bearing issues as is it the case in many 3 liter ram truck and jeeps that they put them in. Winter can be a issue with cold starts on diesel engine but with the Amsoil its never an issue here rarely plug in the block heater. Tony Harrington
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good product
    By  DON,  a  Verified Buyer  on  September 04, 2021
    Good product unfortunately however recent price increase will force me to change brands.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quality product
    By  ANTONIO,  a  Verified Buyer  on  September 04, 2021
    Noticed a difference in the sound of the engine after putting in Amsoil. Runs a lot smoother. Also, shipping was extremely fast!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    BEST DIESEL ENGINE OIL ON THE MARKET
    By  GIANLUCA,  a  Verified Buyer  from  Toronto Ontario   on  September 04, 2021
    Amazing engine oil , only oil I will ever used.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  SERGEY,  a  Verified Buyer  from  Jacksonville,FL  on  September 04, 2021
    The best oil I ever had, extremely low oil consumption on ISX15 engine, runs 50.000miles till drain!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil #1
    By  LOUIS,  a  Verified Buyer  from  Kauai  on  September 03, 2021
    Best products out there highly recommended
    Bottom Line
    Yes, I would recommend this to a friend.
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