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AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

Product code : DMEQT-EA

4.9 star rating Read 1,241 reviews

Customer Rating

4.9

91% would recommend

  • 5 1186
  • 4 41
  • 3 5
  • 2 3
  • 1 6

AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,241 reviews
  • 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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  • 5 star rating
    Quality oil
    By  WAYNE,  a  Verified Buyer  on  May 13, 2024
    Best oil for duramax engines
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best there is...
    By  ROD,  a  Verified Buyer  from  Southwest FL   on  May 12, 2024
    Only oil I have ever used for my trucks.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    2006 Duramax
    By  RAY,  a  Verified Buyer  on  May 11, 2024
    I used the in my 2006 Duramax since it was new! I have 500,000 KLMs on it now and never had any issues with this engine!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    diesel oil
    By  DAVID,  a  Verified Buyer  from  chicago  on  May 10, 2024
    the best oil you can buy.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil super price
    By  TONY,  a  Verified Buyer  on  May 05, 2024
    Love this oil. 6.7 power stroke with 95,000 miles It’s the only oil that’s been used since new
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Max duty oil
    By  Scott,  a  Verified Buyer  from  AZ  on  May 01, 2024
    This is the best oil that you can get. You can see how well it's held up during oil changes. It's the only thing I'll ever use in my super duty.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Bad reward good oil
    By  ADAM,  a  Verified Buyer  from  Utah  on  April 29, 2024
    I exclusively use Amsoil on all my vehicles and toys. The only negative I have is with the rewards. Why aren’t they just built in? I always get an email saying free this or free that but never remember what the code is. Why not just include it?
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product
    By  JASON,  a  Verified Buyer  from  Indianapolis  on  April 29, 2024
    Using it on my 2015 Ram Ecodiesel, It immediately quieted and smoothed out the engine. I'm at 125k miles and no issues. I will continue to send in my oil evaluations for testing and hope to see this truck live a long and happy life. Looking to do my transmission next to prolong longevity and performance. Thank you Amsoil for a great product and for making kits specific to my vehicle, it takes the guess work out of it. Thank you,
    Bottom Line
    Yes, I would recommend this to a friend.
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