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Customer Ratings & Reviews

Heavy-Duty Synthetic Diesel Oil 5W-40

Product code : ADOQT-EA

4.9 star rating Read 54 reviews

Customer Rating

4.9

100% would recommend

  • 5 51
  • 4 3
  • 3 0
  • 2 0
  • 1 0

Heavy-Duty Synthetic Diesel Oil 5W-40

4.9 star rating Based on 54 reviews
  • 5 star rating
    Amsoil Diesel
    By  LOUIE,  a  Verified Buyer  from  Minnesota  on  February 14, 2022
    I've had the same truck and used the same oil and filter for nearly 10 years now. This is a 25,000 mile filter and I change every 2 years with roughly 7,000 on the change. No issues, no oil use, not knocking, no cold weather starting issues and no smoking. I call that a win and will keep this combo going as long as I own the truck. I did take one step down from the Amsoil Signature to the HD Turbo oil but I do not anticipate any problems with that change.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great synthetic oil for 3rd Gen Cummins 5.9!
    By  DAN,  a  Verified Buyer  from  Ohio  on  February 14, 2022
    Very pleased with this purchase. I was hesitant to switch to synthetic, but have had no problems and even a smoother running engine. Cold starts are loads better with this oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Amsoil review
    By  JEFF,  a  Verified Buyer  on  February 12, 2022
    Awesome product love all my Amsoil products run it in many of my toys n cars
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome product
    By  NATE,  a  Verified Buyer  on  February 06, 2022
    My truck purrs with this motor oil. Never skips a beat.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Year round use
    By  CLAY,  a  Verified Buyer  from  Ohio  on  February 03, 2022
    My truck loves this oil. Run it year round
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Greatest oil brand out!
    By  COLLIN,  a  Verified Buyer  from  Idaho  on  January 27, 2022
    I love the quality of ams oil this is what i run in my 1330 hp 6.0 powerstroke sled truck
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Review
    By  JEFFREY,  a  Verified Buyer  on  January 02, 2022
    I gotta say Amsoil is one of the best products I’ve ever used in my bike my truck and everything else I use it in and I gotta say I love having it delivered to my house Best product out there
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quieter than Rotella T6
    By  BENJAMIN,  a  Verified Buyer  on  December 19, 2021
    First time trying Amsoil in the old 7.3 Powerstroke that’s lived it’s life on Delo and Rotella. The engine definitely runs quieter on this than than any of the others, and all temp but especially cold start. No UOA as of yet but it seems very happy with this oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    5w40 orange cap
    By  MARK,  a  Verified Buyer  on  December 09, 2021
    Awesome oil I really am impressed running this in my 12v Cummins with over 300k on the motor starts great in the cold and seems to run very smooth
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quality
    By  ALAN,  a  Verified Buyer  on  December 02, 2021
    I have used Amsoil in the past that I purchased through a friend at work. I have since retried and went online to hopefully purchase Amsoil for my Dodge diesel. I rate this product very high and recommend it to family and friends.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Affordable, yet the very best you can get
    By  DANIEL,  a  Verified Buyer  from  Texas  on  November 26, 2021
    After watching many oil test videos I decided to give it a try and have been extremely happy.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product and delivery time
    By  RUSTY,  a  Verified Buyer  from  Utah   on  November 25, 2021
    Started running in my last 2 diesels, I can’t imagine running anything else. And it’s priced similar to other oils
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great diesel oil
    By  AUGIE,  a  Verified Buyer  from  Tofte Minnesota  on  November 22, 2021
    Use in my Cummins and am more than happy with its longevity and performance
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Expensive motor is worth it!
    By  HAROLD,  a  Verified Buyer  from  Mesquite, NV  on  November 07, 2021
    I've been using Amsoil for over 25 years. You can say, i am familiar with the benefits of their products lol! My wife bought a Dodge 1500 diesel, great truck, but if the engine goes, it's $10,000; just the engine. Running Amsoil, i know it's as protected as possible.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quality lubricants
    By  KENNETH,  a  Verified Buyer  from  Michigan   on  November 05, 2021
    Quality lube for all your diesel needs. I use it in my 6.7 powerstroke and my JD 1025r. The deere is noticeably quieter during warm up with the 5/40!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great stuff
    By  DANIEL,  a  Verified Buyer  from  Western Massachusetts   on  November 03, 2021
    Used to run rotella T6 in my powerstroke diesel. Since I’ve joined the preferred customer program it actually was cheaper to buy amsoil. I’ll never turn back!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good oil for OEM recommended oil change intervals.
    By  JAMES,  a  Verified Buyer  from  Vicksburg, MS  on  October 21, 2021
    I've been using this in my 2004 F150 5.4 since I replaced the cam phasers, timing set and oil pump 2 years ago. Diesel oil was recommended by a mechanic to keep it clean plus a little heavier viscosity. So far so good. Amsoil has always kept my engines cleaner than the other brands even when I used synthetic. I used this for a customers 2018 Ram 3500 6.7.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    👍👍👍👍👍
    By  SERGEY,  a  Verified Buyer  on  October 06, 2021
    👍👍👍👍👍
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    amazing oil
    By  MATTHEW,  a  Verified Buyer  from  texas  on  October 03, 2021
    Amazing oil, pull 16k regularly have no issues with my 6.0
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Run smooth from the start
    By  BALDOMERO,  a  Verified Buyer  on  September 27, 2021
    Sounds quieter from the beginning after you change the oil and runs quite, good product
    Bottom Line
    Yes, I would recommend this to a friend.
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