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

Product code : DEOQT-EA

4.9 star rating Read 1,130 reviews

Customer Rating

4.9

91% would recommend

  • 5 1077
  • 4 40
  • 3 4
  • 2 3
  • 1 6

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

4.9 star rating Based on 1,130 reviews
  • 5 star rating
    Simple the best
    By  JEFFREY,  a  Verified Buyer  from  Ft. Lauderdale   on  July 08, 2023
    It’s the only oil I use in my Diesel truck and motorcycle, Go with the best do your oil changes , it’s the cheapest way to keep anything from happening!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The best oil
    By  JOE A,  a  Verified Buyer  from  Hollywood, FL  on  July 07, 2023
    I have been using this oil for some time now and find it to be the best lubricant for my diesel truck. Everything runs smoothly and quiet.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome Oil!
    By  ANDREW,  a  Verified Buyer  from  Pennsylvania   on  July 02, 2023
    Oil used in 6.4 hemi and 6.2 gmc. Works very well.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Outstanding performance
    By  PAM,  a  Verified Buyer  from  Vermont  on  June 28, 2023
    We are off grid and have a diesel generator. I have used only Amsoil products for this essential equipment. Still humming after 7years of service.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Everywhere
    By  CHARLIE,  a  Verified Buyer  from  Louisiana   on  June 26, 2023
    I have a small horse farm. We use Amsoil Max duty 15w-40 in both tractors, both diesel trucks for long life and protection.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    My 6.0 loves it!!
    By  MICHAEL,  a  Verified Buyer  from  So Cal  on  June 25, 2023
    Ordered before noon and recieved the next day!! My 6.0 loves this stuff. Extremely happy with this oil!! Will continue to recommend to others.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  RICHARD,  a  Verified Buyer  from  Alberta Canada   on  June 25, 2023
    I use this in my 2 diesel trucks and my welding machine
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good
    By  RAMON,  a  Verified Buyer  from  Houston   on  June 23, 2023
    Best motor oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel
    By  KEVIN,  a  Verified Buyer  from  Maryland   on  June 20, 2023
    Quick service , received oil in two working days . Been using since I purchased my vehicle with no issues . Thanks AMSOIL ..
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Product good, customer service?
    By  DAVID,  a  Verified Buyer  from  Olympia wa  on  June 15, 2023
    After I order I received no confirmation email or updates on delivery date. Felt lucky when the order arrived. A bit more communication could go a long way. Like look at the successful online stores maybe.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The Best Oil Period!
    By  TRENT,  a  Verified Buyer  from  Hernando, MS  on  June 15, 2023
    I really can tell a difference using this oil vs any other on my 6.7 Powerstroke. It really runs very smooth. All I'll ever use for oil in my diesel. Very happy.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great engine product
    By  TIMOTHY,  a  Verified Buyer  on  June 14, 2023
    This product meets or exceed any diesel oil product out there! The only engine oil I will ever use in my truck period
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 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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