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AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil

Product code : DEOQT-EA

4.9 star rating Read 1,284 reviews

Customer Rating

4.9

92% would recommend

  • 5 1229
  • 4 41
  • 3 5
  • 2 3
  • 1 6

AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,284 reviews
  • 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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  • 5 star rating
    5w-40
    By  CHRISTOPHER,  a  Verified Buyer  on  October 30, 2024
    I highly recommend this oil for any diesel platform! My 2014 6.7 Cummins loves this oil!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil change
    By  DJ,  a  Verified Buyer  from  Utah  on  October 30, 2024
    Loved the kit! Everything needed was right there in the box for me. Definitely worth the extra money. Thank you.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    periodic oil change interval
    By  KENNETH,  a  Verified Buyer  from  Salmon, Idaho  on  October 29, 2024
    My shipment came on time without a hitch!! Thank You!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Driver
    By  RAMON,  a  Verified Buyer  from  Houston   on  October 28, 2024
    Excellent motor oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Continued use of great products
    By  SCOTT,  a  Verified Buyer  from  Ingram Texas  on  October 24, 2024
    This is the 3rd diesel truck I have owned over the past 20 years. I started using this oil after being re-introduced to the newer and better way to access getting Amsoil products. I have been a long time fan of Amsoil, as I was in the racing community in the 60's -2000's running USAC several divisions and the NASCAR Modified and Super Modified divisions. I had Amsoil as a sponsor for many years of that time period. I stopped using Amsoil after racing due that it was so difficult in finding someone who sold it and would not want to sell you large quantities, if you wanted to buy if for a normal consumer need. Once I found that I a general consumer was able to purchase it from your website and become a discount customer I was all in. I did this in 2015 and have converted all my vehicles to amsoil products. This Diesel oil is great as it has reduced running temp of my motor and turbo, the coolant has increased the cooling quality and has the additive that i no longer have to buy what Ford wants to regen the coolant due to a mental degrading in the engine and cooling system. I also use the Amsoil micro oil filter for each oil change. The truck has just turned over 170K and is still running great. I change the oil every 20K with filter. The truck is a 2012 Ford F350 Super Duty 6.4 Powerstroke Diesel.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    F350 Super Duty
    By  ROBERT,  a  Verified Buyer  from  St. Augustine, FL.  on  October 24, 2024
    I have been using this in my truck since 2018. I like the quality of this over the Motorcraft. And it is actually less than a dollar more per quart the the Motorcraft full Synthetic.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil for my Duramax with 262,000
    By  DAVID,  a  Verified Buyer  from  Michigan   on  October 22, 2024
    Ran this oil in 03 Ford 7.3 and didn't touch the motor till 400,000 at 260,000 with my Duramax and haven't touched the motor. Love this oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature Series 15W-40
    By  BRIAN,  a  Verified Buyer  on  October 21, 2024
    The best oil money can buy
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    great wear 247k miles later
    By  CRESSMAN,  a  Verified Buyer  from  baldwin maine  on  October 21, 2024
    My current truck (2006 lbz duramax) has had Amsoil since its first oil change. Oil has been changed every 25k miles and filter every 10k. At 247,000 miles truck is running strong with zero blow by and burns no oil between changes. My opinion Amsoil makes a great product!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Almost have 200,000
    By  MIKE,  a  Verified Buyer  from  Glenwood Iowa  on  October 20, 2024
    Have been using Amzoil for over 19 years never a oil related problem. I use Amzoil products in everything that requires oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great for cold weather start up
    By  WAYNE,  a  Verified Buyer  from  Pennsylvania  on  October 19, 2024
    I have been using Amsoil 15-40 diesel oil in my 2007 Chevy Duramax since I purchased new in 2007. Never any issues, no oil consumption and easy cold weather start-up.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great for cold weather start up
    By  WAYNE,  a  Verified Buyer  from  Pennsylvania  on  October 19, 2024
    I use this in my Kubota diesel tractor in the winter months. Provides easy cold weather start up.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  PHIL,  a  Verified Buyer  on  October 17, 2024
    I have solely used this oil in my Dodge diesel truck for the last 20 years. Engine still runs like new. It is the only oil for me.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    10/30 Diesel oil
    By  ANDREW,  a  Verified Buyer  from  Missouri   on  October 13, 2024
    Great product i use amsoil in everything this specific oil i use in my M35A2 Kaiser jeep deuce and half 6×6 keeps engine clean less wear runs smoother great product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  JOHN,  a  Verified Buyer  on  October 12, 2024
    It lubricates
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Dayum!
    By  DANIEL,  a  Verified Buyer  from  Texas  on  July 08, 2024
    Best damn oil in the business. You can really tell the difference. After the oil change. My engines running smoother and quieter.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  THOMAS,  a  Verified Buyer  on  July 04, 2024
    Great oil. Holds up well. Seems to keep everything running smooth. 160,000mi and no issues so far
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil !
    By  KYLE,  a  Verified Buyer  from  Barrie  on  July 02, 2024
    Great oil even under extreme heat my oil pressure is still good 👍🏼
    Bottom Line
    Yes, I would recommend this to a friend.
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