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

Product code : DEOQT-EA

4.9 star rating Read 1,209 reviews

Customer Rating

4.9

91% would recommend

  • 5 1154
  • 4 41
  • 3 5
  • 2 3
  • 1 6

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

4.9 star rating Based on 1,209 reviews
  • 5 star rating
    Simply the best oil
    By  MICHAEL,  a  Verified Buyer  from  Quebec Canada  on  June 08, 2024
    I reduce the consomption of oil of my truck in half !
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    2017 powerstroke
    By  SCOTT,  a  Verified Buyer  on  June 07, 2024
    Since using this oil the engine sounds and runs smoother and stays cleaner longer and I get better fuel economy. I trust no other brand. I use amsoil in anything that takes oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Ford 6.0
    By  BEAU,  a  Verified Buyer  on  June 06, 2024
    Used it in two different trucks. And so far impressed with how smooth it sounds running. It seems to be quieter. I have 3k miles on one truck and 500 miles on another. Both trucks are ford 6.0’s. And so far I'm impressed.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil on the market
    By  DYLAN,  a  Verified Buyer  from  NY  on  June 04, 2024
    Been running Ams oil in my 21 f150 3.0 diesel for over 30kmi! I’ve noticed smoother cold starts in subzero temperatures and increased fuel economy! Oil is always shipped very quick right to my door and is well packaged, they provide a nice receipt with date and time stamp which helps with keeping track of my multiple vehicles. Also they usually put a hat , flashlight, tool or sticker in the order free which is nice!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    #1
    By  CALVIN,  a  Verified Buyer  from  Michigan  on  June 03, 2024
    Best oil on the market.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    F250
    By  Mark,  a  Verified Buyer  on  June 03, 2024
    I've been using Amsoil since I bought my truck in 06, pull a 27' camper and have not had any engine issues. Change oil every year whether it needed it or not. Excellent diesel oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel Oil
    By  WADE,  a  Verified Buyer  on  June 02, 2024
    Only thing I use
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    It works
    By  CARLOS,  a  Verified Buyer  from  Monroe NC  on  May 31, 2024
    I have a 2016 ram 1500 eco diesel. The engine is a little quieter. Maybe a slight increase on fuel. I like it and will definitely keep using it. Shipping time was decent.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    40 years using the product.
    By  PIERRE,  a  Verified Buyer  from  Casselman, Ont  on  May 30, 2024
    Have been using Amsoil for over 40 years. Use it in everything.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Full Synthetic Oil
    By  ANTHONY,  a  Verified Buyer  from  Georgia   on  May 27, 2024
    I have been using this oil for about five or six years. I think it’s the best oil out there. I also use the 20w50 V-Twin for my Harley. It’s like Frank’s Red Hot sauce. I put this Sh*t in everything.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Give it a try
    By  JERRY,  a  Verified Buyer  on  May 26, 2024
    I have not had a chance to use it yet but have high expectations by reading test results and comparisons.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil only please
    By  JAMES,  a  Verified Buyer  from  Akron  on  May 25, 2024
    Great oil and filter expensive but worth the mulha
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The best oil money can buy.
    By  ROBERT,  a  Verified Buyer  from  BC, Canada  on  May 25, 2024
    I've owned my 2015 Silverado 3500HD since new and have used Synthetic oil from new, I change my oil every 5000km or 12 months.( I don't put many km's on the truck , only used to pull a 36' travel trailer ) I used to use Rotella T6 5w40 until it got hard to find after Covid and the price shot up. I switched to Amsoil Signature 15w40 and use the Amsoil 20 micron oil filter. My oil used to go black in less than 1000km, but now that I've switched to Amsoil my oil stays much cleaner and is getting better with each oil change. If I add up the cost to use Amsoil per year and multiply that by say 10 years it will only cost me roughly 2000.00. The cost to replace a worn out Duramax is 20,000.00 plus, I would say that it makes good sense.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    it protects the bearing.
    By  COREY,  a  Verified Buyer  on  May 23, 2024
    it protects the bearings very well.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  MICHAEL,  a  Verified Buyer  on  May 21, 2024
    Great oil fast service.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Tick
    By  Gimblenut ,  a  Verified Buyer  from  Florida   on  May 20, 2024
    I had this tick after changing oil. Someone said to try amsoil it should go away. Well it did so what ever you think is the best because Joe said it’s the best because his friend of a friend said so well good luck.
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  • 4 star rating
    1992 5.9 Cummins
    By  ROBERT,  a  Verified Buyer  from  Tucson  on  May 20, 2024
    Oil seems to work great! The oily Oil I use in my Cummins
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best diesel oil out there
    By  Ryan,  a  Verified Buyer  from  Georgia  on  May 19, 2024
    Getting 35k on this stuff in 6.7 cummins with amsoil bypass system on analysis...500hrs on commercial equipment with flawless performance excellent analysis and could push it alot further than I do..
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil in gas eng
    By  JERRY,  a  Verified Buyer  from  Omaha Arkansas   on  May 18, 2024
    Great product so far, running it in my 2021 Nissan Titan
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Return
    By  ALLEN,  a  Verified Buyer  from  512 s main st Shrewsbury pa 17361  on  May 14, 2024
    Third time I connected you. You were supposed to send me a self address ticket to send back a gallon I ordered to much. I’m giving up. But it’s the only oil I use in my truck
    Bottom Line
    Yes, I would recommend this to a friend.
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