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

Product code : DMEQT-EA

4.9 star rating Read 1,550 reviews

Customer Rating

4.9

92% would recommend

  • 5 1485
  • 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 1,550 reviews
  • 5 star rating
    REC
    By  RONALD,  a  Verified Buyer  from  Oregon  on  December 06, 2020
    Great product been using it for years on my 6.7 cummins. The best
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Fast convenient delivery
    By  TIMOTHY,  a  Verified Buyer  from  Florida  on  December 04, 2020
    The truck seems to run and sound better. MPG has increased 10%. I'm also running the all in one.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best synthetic oil on the market
    By  DOUGLAS,  a  Verified Buyer  from  Brazoria Texas  on  December 02, 2020
    I have been using Amsoil for several years and have recommended it to other people that are extremely pleased with this product, we will continue to use Amsoil products and are pleased with the performance from Amsoil products, thanks Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Good product
    By  MATTHEW,  a  Verified Buyer  from  Alabama  on  December 02, 2020
    If you use your truck as a truck and not a grocery getter this is the oil I would recommend. This oil holds up good under heavy towing a cool off times. The lower grade heavy duty started breaking down very fast and only got about 10k miles on it before I noticed oil pressure fluctuations , but this max duty is much better for higher temps and hard working trucks.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Very much recommend these products
    By  William,  a  Verified Buyer  from  California  on  November 30, 2020
    I feel, and most of my friends feel the AMSOIL IS the finest oil on the market. I guess it is what you could call a reference oil, an oil that every other oil manufacturer strives to be like. I've used them all but I have come to trust only AMSOIL. I use their products in all of my vehicles and machinery both diesel and gas, oh....and also my guns.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    By  DOUG,  a  Verified Buyer  on  November 29, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  CORY,  a  Verified Buyer  from  Lamberton, Mn  on  November 28, 2020
    Great oil! Switched my 2009 Peterbilt with the ISX Cummins from mobil delvac 15w-40 to this. Noticed right away that I had less vibration from the engine while sitting in the cab. The oil stays cleaner longer also. I also started running this in my 2008 Silverado 3500 with the Duramax.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  JOSH,  a  Verified Buyer  on  November 26, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  JOSE,  a  Verified Buyer  from  Brownsville,Texas  on  November 26, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  ERNESTO,  a  Verified Buyer  from  Hialeah / Florida  on  November 25, 2020
    The oil I requested for my 2014 Ram/ 6.7 was delivered on time and well packed with no damage . This is the second time I’ve purchased from AMSOIL and will continue in the future . Highly recommend them !
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  BRIAN,  a  Verified Buyer  on  November 22, 2020
    The product speaks for itself
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  CHASE,  a  Verified Buyer  on  November 21, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Dodge Cummins
    By  GEORGE,  a  Verified Buyer  from  Nc  on  November 19, 2020
    I was fortunate to grow up around Amsoil and the benefits of using it I wouldn't use anything else it's the best oil hands down!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    amsol signature-series-max-duty-synthetic
    By  DENNIS,  a  Verified Buyer  from  Wi  on  November 19, 2020
    This 5w40 diesel oil have great protective qualities, and actually made my diesel motor quieter. Due to superior lubrication.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quiet confidence
    By  CHRIS,  a  Verified Buyer  from  MD  on  November 17, 2020
    My 2014 Ram Eco Diesel hums with Amsoil. I have gained in gas mileage and my truck warms up quicker. Love this product - it’s worth the extra $ - invest in your vehicle.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Very High Quality Product
    By  lifer 03,  a  Verified Buyer  from  Stony Point NC   on  November 17, 2020
    Great Oil I would not use any other brand in my Dodge Cummins!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  MIKE,  a  Verified Buyer  on  November 16, 2020
    Great oil doesn’t break down
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  EDGAR,  a  Verified Buyer  on  November 14, 2020
    I’m just going to keep it simple,your not going to find nothing better then this......Amsoil #1
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Dennis,  a  Verified Buyer  from  Dawson Creek  on  November 13, 2020
    My son uses it in his 2004 dodge truck. Highly recamends it.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  DOUGLAS,  a  Verified Buyer  from  Kentucky  on  November 12, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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