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

Product code : DMEQT-EA

4.9 star rating Read 1,541 reviews

Customer Rating

4.9

92% would recommend

  • 5 1476
  • 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 1,541 reviews
  • 5 star rating
    AMSOIL
    By  ABE,  a  Verified Buyer  on  December 07, 2024
    I highly recommend AMSOIL for our vehicles. it’s a premium quality oil.and I can be confident on road trips that my engine will be well lubricated.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great for the 1025R
    By  Dade22,  a  Verified Buyer  on  December 06, 2024
    Dumped the factory oil from my 2024 John Deere 1025r. Maintenance schedule says 200 hours for the first change. No way. I pulled it at 50 hours. It was dark. Some wear metals as expected. I swapped it over to Amsoil 15w-40 Signature Series. First thing I noticed was how easy it was to start and the noise level even dropped. The engine actually seemed to run smoother. I’m a maintenance fanatic. I believe frequent oil changes at the beginning. I will probably pull this out at the 100 hours and then just change it once a year afterwards.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    So far so good 👍
    By  MATT,  a  Verified Buyer  from  New Hampshire  on  November 29, 2024
    I have always used amsoil products and will continue to use them, this diesel oil was exactly what my high horsepower heavy hauling Duramax needed
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature Series 15w40 Syntheric Max Duty Diesel oil
    By  ROBERT,  a  Verified Buyer  on  November 24, 2024
    the Best oil around. Engine seems to run quieter. Also improved gas millage
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  DAVID,  a  Verified Buyer  from  Baltimore   on  November 18, 2024
    Have nothing but good luck with this oil and my Amsoil dealer it’s the best to deal with!! There to help anytime I need it or just to place my order.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I would recommend
    By  CHRIS,  a  Verified Buyer  on  November 18, 2024
    I run this in all my diesel’s trucks and Volkswagen diesel car work very well for me
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil change
    By  DANA,  a  Verified Buyer  from  New phila  on  November 17, 2024
    Exactly what I ordered and came before delivery date which is very good
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Don’t know what you’re asking
    By  GERALD,  a  Verified Buyer  on  November 14, 2024
    Good product and service
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    No oil is better—none!
    By  STURE,  a  Verified Buyer  from  Elk River, MN  on  November 12, 2024
    No oil is better—none! I have used this product since May 2020. My diesel engine purrs like a content kitten, and I have gone 15K miles between oil changes.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    15-40 diesel oil
    By  TONY,  a  Verified Buyer  from  Maryland  on  November 11, 2024
    I have been using this oil in my 2015 3500 Silverado with a Duramax diesel. I started using the oil at 10,000 miles. I now currently have 198,000. It doesn’t use oil and it does not leak oil. I change the oil every 7500 miles. Absolutely love this product.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel Syn. Oil
    By  BRIAN,  a  Verified Buyer  from  Az.  on  November 10, 2024
    Great oil to use on all your toys !
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil on the market
    By  LUIS,  a  Verified Buyer  from  Live Oak, TX   on  November 10, 2024
    This is seriously the best oil on the market for gas and diesel trucks. Comes in just a few days. I will always use Amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Product review
    By  DARRYL,  a  Verified Buyer  from  Luther, MI.  on  November 10, 2024
    Amsoil is an incredible product that really delivers both in performance and customer service. I highly recommend all of their products.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil quality
    By  RADU,  a  Verified Buyer  from  Portland Oregon   on  November 09, 2024
    Best oil to use.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil on the market
    By  DAVID,  a  Verified Buyer  from  Michigan   on  November 09, 2024
    We use it because it's the best stuff on the market.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Oil
    By  Teegan,  a  Verified Buyer  from  Clovis, CA  on  November 04, 2024
    I use this oil in my truck and there is a noticeable difference in hot oil pressure. With other oils the hot oil pressure is about 38 PSI and with AMSOIL 15W-40 the hot oil pressure is about 42 PSI. The cold start valve noise is noticeable quieter with the AMSOIL than with other oils.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best in the business
    By  NICK,  a  Verified Buyer  from  Canaan   on  November 04, 2024
    Been using these products for over 20 years highly recommend best in the business AMSOIL. We got out of a 89 Ford straight, six 450,000 miles. it actually still started, but motor had no more power
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great stuff
    By  BEN,  a  Verified Buyer  from  Iowa   on  November 02, 2024
    Great oil! I’ve been running in my 2017 duramax since it was new! 200k and going strong!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Flawless
    By  Jason,  a  Verified Buyer  from  Wyoming   on  November 01, 2024
    I absolutely love the protection and performance from amsoil. My truck runs so much better and actually see a slight increase in mpg since switching to amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    It really does work
    By  ERICK,  a  Verified Buyer  from  Arizona  on  October 31, 2024
    My 97 power stroke always made a lot of deisol rattling noises, especially when cold..Amsoil made it quiet and ran much better...I pulled a heavy 8 k camper, 2 k miles and I am sure fuel milage was better.. definitely have mo power...in the big picture it's cheaper to use Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
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