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AMSOIL 5W-40 Heavy-Duty 100% Synthetic Diesel Oil

Product code : ADOQT-EA

4.9 star rating Read 93 reviews

Customer Rating

4.9

98% would recommend

  • 5 88
  • 4 5
  • 3 0
  • 2 0
  • 1 0

AMSOIL 5W-40 Heavy-Duty 100% Synthetic Diesel Oil

4.9 star rating Based on 93 reviews
  • 5 star rating
    Good in cold weather
    By  AARON,  a  Verified Buyer  from  Nothing west Ont Canada   on  February 23, 2024
    Run it in my 1998 chevy k2500 6.5 diesel starts easily in the winter months
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Hands down best diesel oil available!
    By  TIM,  a  Verified Buyer  from  Slidell, La  on  February 09, 2024
    Have driven this truck very hard towing a 5th wheel all over country 8k oil changes with Amsoil has kept my Titan xd 5.0 Cummins running strong for 150k +
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    So amazing highly recommend for a Cummins diesel
    By  Quaid,  a  Verified Buyer  from  MT  on  January 20, 2024
    Amazing product very very good oil pressure and runs smooth for my Cummins 24 valve 5.9
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil for my RAM Cummins
    By  FRANCISCO,  a  Verified Buyer  from  New Jersey   on  January 16, 2024
    I mean Amsoil speaks for itself. From the moment you pour it down in your engine, you feel the difference. Just knowing that your motor has quality oil inside of it makes you feel some type of way. Do your self a favor and stick with amsoil in all your lubrication needs!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    My 6.0 Powestroke loves it.
    By  LEE,  a  Verified Buyer  on  January 12, 2024
    Can’t go back to another brand. Engine runs so much smoother.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Nice Diesel Oil
    By  JIM,  a  Verified Buyer  on  January 04, 2024
    I use this oil in my 2022 F350 6.7 Powerstroke. Always starts right up, no noise and better fuel economy than the factory fill oil. When you compare Diesel oil specs, Amsoil is tough to match, let alone beat.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Always a winner
    By  JOHN,  a  Verified Buyer  from  Virginia   on  December 31, 2023
    Satisfied as always, I use this oil in all my diesels in conjunction with a bypass filter (bp90).
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Winter oil
    By  DARYL,  a  Verified Buyer  from  Parkland County  on  December 30, 2023
    Always use in winter then 15w 40 in summer
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I only use Amsoil
    By  AUGIE ,  a  Verified Buyer  from  Isabella Mn   on  December 21, 2023
    Great oil for my Cummins love it!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 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
    Smooth
    By  SHANE,  a  Verified Buyer  on  November 16, 2023
    Best lube in the busy
    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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