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

Product code : DMEQT-EA

4.9 star rating Read 1,544 reviews

Customer Rating

4.9

92% would recommend

  • 5 1479
  • 4 45
  • 3 9
  • 2 3
  • 1 8

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

4.9 star rating Based on 1,544 reviews
  • 5 star rating
    AWESOME Sauce!!
    By  NICHOLAS,  a  Verified Buyer  on  May 21, 2021
    The only oil products I use!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Worry-free towing
    By  RICHIE,  a  Verified Buyer  from  ARKANSAS  on  May 21, 2021
    I use my 2004 GMC 2500HD with the 6.6 Duramax to tow a 32' living quarters horse trailer. The truck is also my daily driver so I need dependability whether running errands or pulling the trailer. I have been using Amsoil since I bought the truck used with 88,000 miles on it. I now have 242,000 on the odometer. All of my fluid are also Amsoil and I have the dual remote oil filtration system. The Duramax purrs and never runs hot, even pulling up long grades.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great engine lubricant !
    By  James,  a  Verified Buyer  from  Texas  on  May 21, 2021
    I have been using synthetic oils from Amsoil for years with great success and when I purchased a Dodge diesel pick-up I immediately put the Amsoil synthetic oil in it also. I trust Amsoil products completely and recommend them all the time.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil
    By  LIVIU,  a  Verified Buyer  from  Drums Pa  on  May 21, 2021
    Great quality oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Nice for Duramax
    By  BOBBY,  a  Verified Buyer  on  May 01, 2021
    Actually added a couple of mpg on my 2003 Duramax. Like the product.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The Best
    By  JEFF H,  a  Verified Buyer  on  April 30, 2021
    Trucks are expensive buy the best oil and save money
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Perfect application
    By  LESTER,  a  Verified Buyer  from  Brighton TN  on  April 25, 2021
    Even the local Ford place recommends and will service my F250 with Amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil review
    By  STEVE,  a  Verified Buyer  from  Munford TN  on  April 24, 2021
    Best oil on the market love it
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Good product
    By  NEWTON,  a  Verified Buyer  from  Weatherford tx   on  April 24, 2021
    Good oil, have over 7000 miles and still clean for a diesel.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil I've tried
    By  TERRY,  a  Verified Buyer  from  IA  on  April 23, 2021
    BETTER COLD STARTS AND WARM WEATHER PRESSURE THAN SYN ROTELLA I CAN'T THINK OF ONE THING I DONT LIKE ABOUT THIS OIL
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil for your diesel.
    By  MILES,  a  Verified Buyer  on  April 22, 2021
    As always amsoil performs great. Cold starts are much easier, and the oil flows much more readily based on oil pressure readings. I’ve ran amsoil products in everything from motorcycles to diesel trucks and can’t recommend it enough.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  BILLY,  a  Verified Buyer  on  April 19, 2021
    Absolutely the best oil I’ve ever used.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product fast shipping
    By  ERIC,  a  Verified Buyer  from  Pennsylvania   on  April 19, 2021
    Love this product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil Products
    By  LAURENCE,  a  Verified Buyer  on  April 18, 2021
    I have been using Amsoil products for 30 years. Need I say more???
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Products
    By  DOUG,  a  Verified Buyer  from  Lethbridge   on  April 17, 2021
    I love being able to order direct from amsoil . It is extremely convenient and the quality of the products is second to none.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The best oil that I can afford
    By  DAN,  a  Verified Buyer  from  Kentucky   on  April 15, 2021
    I use this oil in my freightliner Cascadia and in my 2017 powerstroke with an Amsoil bypass filter with regular oil analysis this oil has proven itself.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Cant beat the price!
    By  BOBBY,  a  Verified Buyer  from  TX  on  April 15, 2021
    I like to try and test oils in my vehicles. Ever since my oil analysis kept coming back positive from a 3rd party oil analyst company, I have stuck with AMS. It seriously is not snake oil. And my trucks love it. Idle quiter and sustained fuel economy improvement. Meaning that it stays constant with fuel economy. It doesn’t jump up or down, just level.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great diesel oil
    By  ALFREDO,  a  Verified Buyer  on  April 12, 2021
    Overall great oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    best stuff in the market
    By  RONNIE,  a  Verified Buyer  from  lake Anna   on  April 12, 2021
    best stuff on the market use it in my truck and both my Harleys
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Go to in Ford 6.7 powerstroke
    By  CHRIS,  a  Verified Buyer  from  new Hampshire  on  April 11, 2021
    When you ante up $10K for the industries most powerful diesel you want to take steps to ensure it is well kept. Have been using thee Signature Oil with the Amsoil by-pass system. Have been happy with the results. Highly recommended.
    Bottom Line
    Yes, I would recommend this to a friend.
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