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Heavy-Duty Synthetic Diesel Oil 5W-40

Product code : ADOQT-EA

4.9 star rating Read 82 reviews

Customer Rating

4.9

98% would recommend

  • 5 77
  • 4 5
  • 3 0
  • 2 0
  • 1 0

Heavy-Duty Synthetic Diesel Oil 5W-40

4.9 star rating Based on 82 reviews
  • 5 star rating
    HD Amsoil fir diesel
    By  JEFF,  a  Verified Buyer  from  Oregon  on  December 06, 2023
    Started using Amsoil in my diesels years ago, quit spending money on nanoborate additives. Works great
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Purchases with promos
    By  GREG,  a  Verified Buyer  on  October 21, 2023
    It's nice to have promos. I love the products, but when the promo item isn't sent, it's a little frustrating. I ordered ahead of my scheduled time just to receive the promo item, so when it didn't come.............still love the oil though.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Diesel oil
    By  BRENT,  a  Verified Buyer  from  South Dakota  on  October 02, 2023
    Great product! When I first got my powerstroke 4 yrs ago I had a tiny valve click. Used the 5-40 heavy duty diesel oil, tick gone!!! I won’t use anything else ! I used amsoil from my first oil change in my 6.4 powerstroke till now I highly suggest it!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    6.0 powerstroke
    By  JEFF,  a  Verified Buyer  from  Oregon  on  September 15, 2023
    After trying many synthetics on the market, I got the best performance out of amsoil for my 6.0 powerstroke
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Ram Eco-Diesel oil
    By  ANTHONY,  a  Verified Buyer  from  New Mexico  on  September 09, 2023
    2015 Ram 1500 Eco-diesel Running this oil because this engine needs the best to survive with the extremes these engines see with emission requirements!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    best
    By  SERGEY,  a  Verified Buyer  on  July 31, 2023
    best
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  • 5 star rating
    Diesel oil
    By  RON,  a  Verified Buyer  on  June 25, 2023
    Was delivered on time 3gals ordered going in to a Cummins 6.7 which holds 12qts then the oil was put in it was 1 quart low . 11quart
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil. Great program
    By  JASON,  a  Verified Buyer  from  Calgary Alberta   on  May 29, 2023
    Been using Amsoil for about 8 years now in various vehicles. What drew me in was the product quality and reputation. I work a lot in remote areas and don't always have access to power for my block heater. Extreme cold weather starts have been made easier since I switched to the 5w-40.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome
    By  AUGUST,  a  Verified Buyer  from  Isabella mn  on  April 28, 2023
    The best Diesel motor oil I have ever used it’s awesome
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Feels Good
    By  BRANDON,  a  Verified Buyer  on  April 13, 2023
    It just feels good knowing I'm putting in quality oil in my truck! Oil is the lifeblood of your Truck. Take care of it
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil !!
    By  CRAIG,  a  Verified Buyer  on  March 27, 2023
    Love this oil motor runs smooth. Amsoil is a great product.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product been using it for awhile now
    By  JARRED,  a  Verified Buyer  on  March 16, 2023
    Great product been using it for awhile now!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    4x 5-40 diesel oil
    By  DUANE,  a  Verified Buyer  from  lakewood ca   on  February 15, 2023
    amsoil is all in use in everything i drive
    Bottom Line
    No, I would not recommend this to a friend.
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  • 5 star rating
    Great product
    By  Eric,  a  Verified Buyer  from  MT  on  January 03, 2023
    Great product. Takes the smoke out of the back end and makes cold starts effortless.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  JIM,  a  Verified Buyer  from  Arizona  on  December 31, 2022
    I used this oil for my first oil change (2022 F-350 Diesel). The engine starts and runs quieter than with the factory fill.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil
    By  MATT,  a  Verified Buyer  on  December 31, 2022
    Love this stuff
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The good stuff
    By  DAN,  a  Verified Buyer  from  Massachusetts   on  December 25, 2022
    Used to run rotella t6 but switched to this stuff ever since I discovered the preferred customer program and will never go back! Run it in my powerstroke and my tractor now as well
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil Quality
    By  JIM,  a  Verified Buyer  from  Florida  on  December 25, 2022
    Many oils are not described about the abilities to protect the engine. Amsoil does. As well with filters like the two sets of Amsoil double filters I have installed on two trucks their filters are far superior in cleaning oil. Most products sold today are poor quality with advertising. Amsoil has stuck to consumer education and better products. All our equipment uses Amsoil oil and filters in order to avoid other oil company scams. We removed the 2015 6.7 diesel engine oil pan on a Ford F350 and with using Amsoil the pan inside was 100% clean, zero deposits. A larger oil pan was installed, no engine problems.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil
    By  DOUGLAS,  a  Verified Buyer  on  December 05, 2022
    Don't waste your money on cheap oil, in the end you will save money.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  PAUL,  a  Verified Buyer  from  Moses Lake   on  November 28, 2022
    It's a great product and a good value.
    Bottom Line
    Yes, I would recommend this to a friend.
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