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AMSOIL 15W-40 Heavy-Duty 100% Synthetic Diesel Oil

Product code : ADPQT-EA

5 star rating Read 207 reviews

Customer Rating

5

98% would recommend

  • 5 200
  • 4 5
  • 3 1
  • 2 1
  • 1 0

AMSOIL 15W-40 Heavy-Duty 100% Synthetic Diesel Oil

5 star rating Based on 207 reviews
  • 5 star rating
    Best oil on the Market!
    By  Jim,  a  Verified Buyer  from  CA  on  January 19, 2025
    I have used 15-40 in my Chevy Duramax since I bought it, quieted it down, lowered temps and overall exceeded my expectations!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product made in USA !
    By  KERRY,  a  Verified Buyer  from  Oregon   on  January 18, 2025
    Great company great product speedy delivery made in the USA!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Great for my 07 5.9 Cummins
    By  BRAD,  a  Verified Buyer  on  January 14, 2025
    I do one oil change a year on my 2007 Dodge Cummins, and this oil is just incredible. Probably a little overkill for the annual mileage but worth every penny.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The good stuff
    By  LUKE,  a  Verified Buyer  on  January 13, 2025
    Best of the best
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  PETER,  a  Verified Buyer  from  Given   on  January 01, 2025
    This oil is a great price and i recommend this product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Oil you can buy
    By  NATHEN,  a  Verified Buyer  on  December 27, 2024
    This oil is the best you can get. I trust it with all my engines which include diesel, gas and outboard boat. Can’t go wrong with their oil and their other products.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil out there. Better than Mobile one in my opinion
    By  JOHN,  a  Verified Buyer  from  700 holly hills   on  December 19, 2024
    See above
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent performance and long lasting.
    By  ECODiesel,  a  Verified Buyer  from  Oklahoma   on  December 07, 2024
    Been running this in my Ram 2500 with the cummins for a while. Oil stays clean and if you run a bypass system you can run this oil for 20K plus miles.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Synthetic oil out there!
    By  WENDELL,  a  Verified Buyer  from  utah  on  December 06, 2024
    I put Amsoil in everything I own. People complain about the cost, but I can go 1 year+ between oil changes in my Duramax Diesel. People don't realize engines with turbos break down oils a lot quicker because of the intense heat (1700 degrees). Oil circulates through the turbo, Amsoil does not break down like other oils in that kind of temperature.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Review
    By  RICHARD,  a  Verified Buyer  from  Ca.  on  December 01, 2024
    Have used Amsoil in my Dodge Cummings engine for seven (7) years. Maintains higher oil pressure at an idle than other engine oils. When having the injectors and valves adjusted, my mechanic tells me my upper engine is the cleanest he has ever see that has 228,000 miles on it. Rich Aubuchon owner
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    15-40
    By  JEREMY,  a  Verified Buyer  from  S.Illnois  on  November 28, 2024
    Happy with the oil I change it at 5k.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Incredibly Happy!
    By  JORDAN,  a  Verified Buyer  from  TN  on  November 27, 2024
    This is the only oil I have ran in my truck since the day I bought it - the truck currently has 267,000 miles of all this oil in it. Very pleased!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Just use it.
    By  ANDREW,  a  Verified Buyer  from  California   on  November 19, 2024
    400,000+ miles on my Duramax thanks to this oil!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best 100% Synthetic Diesel Oil made
    By  WY216,  a  Verified Buyer  from  Big Horn, WY  on  November 17, 2024
    It is without a doubt the best engine oil made for diesel owners. The truck runs cleaner, cooler, and longer between oil changes. I highly recommend it! I have 260,000 miles on my Ford 6.0 without any oil-related problems.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Longevity
    By  Avalon ,  a  Verified Buyer  from  Us East Coast   on  November 16, 2024
    AMSOIL 15W40 has been the only oil used in my 1999 Cummins 6BT5.9 along with their filters. EVERY oil analysis from Blackstone has come back with zero negatives. I will always use AMSOIL products in my engines.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Use the best forged the rest
    By  WAYNE,  a  Verified Buyer  from  Stroudsburg pa  on  October 28, 2024
    There is no substitute. There is only one oil AMSOIL
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil synthetic
    By  PAT,  a  Verified Buyer  from  Ontario  on  July 07, 2024
    Fast shipping. Great oil. Will always run AMSOIL 100% synthetic
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Truck oil
    By  WALTER,  a  Verified Buyer  from  Fenton, MI  on  June 14, 2024
    Have used this for quite a few years and had great results. Will use it on this truck and more to come. Love this stuff.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Truck oil
    By  Jeff,  a  Verified Buyer  from  Overton NV  on  June 09, 2024
    Great oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Review
    By  ROBERT,  a  Verified Buyer  from  Rancho Cucamonga   on  June 07, 2024
    It’s a great blend of oil and easy to order online
    Bottom Line
    Yes, I would recommend this to a friend.
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