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Customer Ratings & Reviews

Signature Series Max-Duty Synthetic Diesel Oil 15W-40

Product code : DMEQTC-EA

4.9 star rating Read 841 reviews

Customer Rating

4.9

88% would recommend

  • 5 797
  • 4 33
  • 3 3
  • 2 3
  • 1 5

Signature Series Max-Duty Synthetic Diesel Oil 15W-40

4.9 star rating Based on 841 reviews
  • 5 star rating
    oil
    By  TOM,  a  Verified Buyer  on  May 11, 2022
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    the only oil I use in my truck
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Second to none!
    By  DANE,  a  Verified Buyer  on  May 11, 2022
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    The max duty product is second to none. Use with confidence. If you’re looking for a 5w-30/40 synthetic oil and truly want the best (actual synthetic blend) on the market that’s available to order and will arrive at your door fast…look no further.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    AMSOIL Full Synthetic Diesel Motor Oil
    By  MAX,  a  Verified Buyer  on  May 10, 2022
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    I highly recommend this motor oil for all your diesel trucks.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quieten that engine
    By  BILLY,  a  Verified Buyer  from  Va  on  May 10, 2022
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    This is the second time if used thin in my 2019 John Deere 2025r. It definitely makes the engine quieter and noticed a little smoother as well!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Sweet Oil
    By  THOMAS,  a  Verified Buyer  from  Iowa  on  May 07, 2022
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    With the current inflation ridden prices on Diesel oil, Amsoil is no longer high priced. Signature series is great Oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature 15w40 diesel oil
    By  ED,  a  Verified Buyer  on  May 06, 2022
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    Always performs well reduced engine temperatures when towing with my truck dodge 2500 Cummins diesel also my sons 6.7 ford while towing keeps temperatures down, I have been a dealer as well as a preferred customer 13 years Using Amsoil and still going strong Motorcoach, tractors and small engines
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent product
    By  JACKIE,  a  Verified Buyer  from  Maryland   on  May 06, 2022
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    Excellent product and quick delivery
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  CHRIS,  a  Verified Buyer  from  Oklahoma  on  May 06, 2022
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    Great oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 1 star rating
    It’s probably fine.
    By  BRETT,  a  Verified Buyer  on  May 05, 2022
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    I had ordered 15W40, I received 5W40 by mistake, I had to pay return shipping and even though I had asked them to exchange it, they refunded my money and I had to reorder what I originally ordered in the first place. Product great, customer service awful.
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  • 5 star rating
    Great transaction with great oil
    By  Charles,  a  Verified Buyer  from  KY  on  May 04, 2022
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    Great oil delivered fast
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Tim
    By  Stew,  a  Verified Buyer  on  May 03, 2022
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    Best oil ever!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Love this oil
    By  JEFFREY,  a  Verified Buyer  from  Michigan   on  May 03, 2022
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    I switched to this oil from Shell Rotella and I can say that I love it. Reduced engine noise, better gas mileage, etc. It’s pricey but it’s worth it.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Robust & Durable
    By  Dee,  a  Verified Buyer  on  May 02, 2022
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    From the moment I transition to amsoil diesel oil, my engine's performance as be spectacular, its as if all it's lubrication needs has finally been met, thanks to diesel oil amsoil outstanding performance
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil signature diesel oil
    By  JOHNNY,  a  Verified Buyer  from  Bronson, fl   on  May 01, 2022
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    Absolutely the best. Period.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good Stuff
    By  BRANDAN,  a  Verified Buyer  on  May 01, 2022
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    Will be running in the truck until she rots into the ground.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good product at a decent price.
    By  TREVOR,  a  Verified Buyer  on  May 01, 2022
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    Good product for a decent price.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Always satisfied!
    By  MARLON,  a  Verified Buyer  from  California  on  April 30, 2022
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    Amsoil is #1!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good product
    By  DAVID A,  a  Verified Buyer  on  April 28, 2022
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    I've been using amsoil in my new 6.7 Ford diesel for 2 years. I use it in all my trucks we average 9,500 miles a month a truck per month.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome product and fast delivery!
    By  RICHARD,  a  Verified Buyer  from  AZ  on  April 25, 2022
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    My product arrived fast. Instantly noticed a reduction in noise engine in my dodge Cummins. Runs smoother as well! Also put Amsoil synthetic oil in my 2006 Yamaha Rhino. Same great results!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil synthetic diesel oil
    By  ShastaRose,  a  Verified Buyer  from  Southern Oregon  on  April 25, 2022
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    This is a superior synthetic oil. Great for vehicles that are in extreme weather conditions and are used for heavy work.
    Bottom Line
    Yes, I would recommend this to a friend.
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