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

Product code : DMEQTC-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
    2.5 Gallon size
    By  SCOTT,  a  Verified Buyer  on  January 20, 2021
    I didn't realize there was such a size until I browsed the Amsoil site. I run the PPE filter on my Duramax so a big jug and small jug does the job with no leftovers. So convenient to get order sent to my home.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Only oil for my trucks
    By  ANDREW,  a  Verified Buyer  on  January 19, 2021
    Love this oil, I have been using it for years
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  LORRAINE,  a  Verified Buyer  from  Ontario,CA  on  January 19, 2021
    Runs smooth no oil burn
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Satisfied as Usual with Amsoil
    By  SCOTT,  a  Verified Buyer  from  Mississippi  on  January 19, 2021
    Quick delivery for a superior product, use Amsoil in all my vehicles
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    By  ALBERT,  a  Verified Buyer  from  Cold Lake, Alberta, Canada  on  January 19, 2021
    I did find that this lubricant worked on reverse in saying it will increase fuel mileage, my with backwards. I still continue using this oil for my 2015 GMC 3500 HD Diesel engine
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    best oil
    By  RODNEY,  a  Verified Buyer  on  January 19, 2021
    best oil fastest service
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    best ol
    By  RODNEY,  a  Verified Buyer  on  January 19, 2021
    best oil and fastest service
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The best
    By  WAYNE,  a  Verified Buyer  from  Chilliwack  on  January 18, 2021
    Tried many oils when I got my Duramax and this is the only stuff that takes the ticking away
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  MIKE,  a  Verified Buyer  from  Los Angeles   on  January 18, 2021
    There’s a lot of BS that gets passed around about what motor oil is the best. That being said, I run Zrod oil in any car I work on with flat tapper lifters. Several times I’ve had friends buy themselves a new toy/project car and the first thing we do is change all the fluids. Running Zrod after mystery oil actually makes the engines quieter! I’ve had several engines with lifter ticks become silent with just an oil change.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The absolute best.
    By  KEN,  a  Verified Buyer  on  January 18, 2021
    This oil takes all the worry if your is doing it’s job. Just use this and there is none better
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  PATRICK,  a  Verified Buyer  on  January 18, 2021
    I live out of my RV and refuse to take any chances. Great oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  CHARLES,  a  Verified Buyer  on  January 18, 2021
    Bottom Line
    No, I would not recommend this to a friend.
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  • 5 star rating
    By  Robert,  a  Verified Buyer  from  New York  on  January 18, 2021
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  EVERETT,  a  Verified Buyer  from  New York  on  January 09, 2021
    I have used Amsoil for my diesel truck for a couple of years now and couldn't be happier with its performance. I have had no issues with the truck starting and it runs strong i pull a 42 foot fifth wheel camper with ease. It makes me feel good every time I start my truck to know it is being lubricated properly without worrying if my oil is breaking down when I change the oil the old oil still appears to be holding up well after 10,000 miles. Cost a little more up front but I feel it is well worth the money.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  BRENT,  a  Verified Buyer  on  January 08, 2021
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  MICHAEL,  a  Verified Buyer  on  January 08, 2021
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome oil
    By  JORGE,  a  Verified Buyer  from  Miami, FL  on  January 06, 2021
    Great synthetic oil. I have used this oil in my diesel truck since it rolled out of the dealer.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Never lets me down
    By  DEAN,  a  Verified Buyer  from  Virginia  on  January 05, 2021
    I regularly lab test oil samples from my truck. Every one comes back great. This oil gets abused hauling around 11,000 lbs in the summer heat and I rarely see oil temps crest 225° even in August. Amsoil keeps the diesel happy all year long!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent product
    By  KASEY,  a  Verified Buyer  from  SW Louisiana  on  January 02, 2021
    A good quality product for the price. Very timely shipping.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil l5p
    By  JEFFREY,  a  Verified Buyer  from  Cape coral Florida   on  December 31, 2020
    Awesome product, highly recommend for all diesel drivers
    Bottom Line
    Yes, I would recommend this to a friend.
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