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Customer Ratings & Reviews

Signature Series Max-Duty Synthetic Diesel Oil 5W-40

Product code : DEOQT-EA

4.9 Read 672 reviews

Customer Rating

4.9

86% would recommend

  • 5 636
  • 4 29
  • 3 1
  • 2 3
  • 1 3

Signature Series Max-Duty Synthetic Diesel Oil 5W-40

4.9 Based on 672 reviews
  • 5
    Amsoil 15w40 diesel oil
    By  RONNALLE,  a  Verified Buyer  from  Parker  on  October 15, 2021

    Describe the issue

    Up to 25000 miles for next oil change. With amsoil oil filter and product. Recommend oil sample's during long drain interval.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Excellent
    By  MATTHEW,  a  Verified Buyer  from  New Jersey   on  October 13, 2021

    Describe the issue

    Excellent product, first time running AMS oil I noticed my diesel run smoother immediately.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    oil change
    By  LUIS,  a  Verified Buyer  from  port barrington  on  October 12, 2021

    Describe the issue

    great oil love it
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Runs like new
    By  SAMUEL,  a  Verified Buyer  from  Nyc  on  October 09, 2021

    Describe the issue

    Keeps my trailblazer Ss running strong
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Awesome Product
    By  act,  a  Verified Buyer  from  Maplesville  on  October 08, 2021

    Describe the issue

    I will not use anything else, Works great, Highly Recommend
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Oil
    By  STEVE,  a  Verified Buyer  from  Michigan   on  October 08, 2021

    Describe the issue

    I love this product has not let me down
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Awesomeness
    By  ASA,  a  Verified Buyer  on  October 08, 2021

    Describe the issue

    Always makes my Truck run like new every time I change the oil. That’s not an overstatement either, I’ve used royal purple for years and then I decided to switch over due to all my buddies who I know run Amsoil. Best that money can buy
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Great Product
    By  Ray,  a  Verified Buyer  from  Nebraska   on  October 04, 2021

    Describe the issue

    Shipping was quick. Great buy. Comparable to what’s at your local stores. I have both engine oil and differential oil in my truck. Love them both.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Oil
    By  MICHAEL,  a  Verified Buyer  from  Winchester Virginia   on  October 04, 2021

    Describe the issue

    Great oil
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Great oil, all I use in everything.
    By  MYRON,  a  Verified Buyer  from  Alberta Canada  on  October 04, 2021

    Describe the issue

    This is great oil, I use Amsoil products in all my vehicles and love it! Wouldn't use anything else.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Great
    By  PHILIP,  a  Verified Buyer  on  October 03, 2021

    Describe the issue

    Will use again
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    less oil consumption
    By  BERNARD,  a  Verified Buyer  from  charlotte NC  on  September 29, 2021

    Describe the issue

    I have a diesel with over hundred fifty thousand miles on it and uses less than a half qt. between oil changes. This is one great oil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Good
    By  GAVIN,  a  Verified Buyer  from  Wisconsin  on  September 25, 2021

    Describe the issue

    My while family has ran this in their vehicles for years. It's all we run. Good oil good price.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 4
    Good but very expensive
    By  TERRY,  a  Verified Buyer  from  New Mexico  on  September 25, 2021

    Describe the issue

    Great oil so far but it is very expensive and not happy about price increase
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Diesel oil
    By  JASON,  a  Verified Buyer  from  Shortsville ny  on  September 24, 2021

    Describe the issue

    Best oil on the market
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Signature Series SAE 5W-40
    By  MANUEL,  a  Verified Buyer  from  Kingsville,Tx  on  September 20, 2021

    Describe the issue

    I have been using Signature Series 5W-40 Diesel Oil since 2018 and I have to say that It’s the best synthetic oil out there. It’s the only oil I use in my 2013 Ford F-250 6.7 liter turbo diesel. I highly recommend this oil for your diesel truck.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 4
    Transport Driver
    By  JEREMY,  a  Verified Buyer  from  TN  on  September 19, 2021

    Describe the issue

    I have been using Amsoil for years now and currently have close to 350k miles on my Ram 3500 without any engine issues. I would recommend this oil if you want an oil that can withstand the extra temperature and stress put on an engine running 11-12 hrs. a day 2-3 weeks a month.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Excelente quality the best oil for my Duramax
    By  LUIS,  a  Verified Buyer  from  Homestead   on  September 19, 2021

    Describe the issue

    I really love the oil quality , the Duramax engine work amazing
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Signature Series 5w-40 Diesel OIl
    By  BEN,  a  Verified Buyer  from  Tulsa  on  September 16, 2021

    Describe the issue

    Been using this oil in my 2019 Ford F350 Super Duty Lariat with the 6.7L Powerstroke Diesel engine and so far so good. Engine runs clean and smooth with zero issues. This is really good oil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    AMSOIL DIESEL OIL
    By  ROBERT,  a  Verified Buyer  from  GEORGIA  on  September 15, 2021

    Describe the issue

    Pulling a 15k # boat, you want to have the best protection you can give your engine! This is the best you can get!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?