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

Product code : DMEQTC-EA

  • Outstanding extreme-pressure protection
  • Delivers 6X more wear protection1
  • Maintains proper viscosity (thickness)
  • Minimizes oil consumption
  • Maximizes fuel efficiency
  • Excels in extreme temperatures
  • Confidently extend drain intervals

     

    1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation

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



Developed to protect the horsepower diesel enthusiasts crave and extend the life of hard-working commercial equipment in the most severe conditions. Signature Series synthetic technology delivers max-duty protection in on- and off-road applications.

See the Product Data Bulletin for full details.

MAXIMUM ENGINE PROTECTION

  • Delivers 6X more wear protection,1 delivering extra protection so you can push your diesel with peace of mind
  • Provides long-lasting wear protection, keeping cylinder liners looking like new2
  • Delivers up to 60 percent better turbo cleanliness3
  • Withstands the extra demands you place on the turbo when pulling heavy loads or updating the tune for maximum horsepower
  • Provides up to 2X better rust protection4

1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation
2Based on independent testing of AMSOIL 5W-30 Signature Series Max-Duty Synthetic Diesel Oil and a leading conventional 15W-40 diesel oil using the Detroit Diesel* DD13 Scuffing test for specification DFS 93K222.
3Based on specification standards of CAT C13 2nd Ring Top Land Carbon testing
4Based on industry standard testing using the NMMA FC-W Rust Test.


Delivers More Wear Protection

Third-party testing shows Signature Series Max-Duty Synthetic Diesel Oil delivers 6X more protection against wear than required by Detroit Diesel’s* standard.II

IIBased on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation.
*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use.


AMSOIL Fights Wear

AMSOIL delivers powerful engine protection. How good is it? In third-party testing compared to a leading brand, AMSOIL provided long-lasting wear protection, keeping cylinder liners looking like new.DD

AMSOIL Fights Wear – AMSOIL delivers powerful engine protection. How good is it? In third-party testing compared to a leading brand, AMSOIL provided long-lasting wear protection, keeping cylinder liners looking like new.

DDBased on third-party testing of AMSOIL 5W-30 Signature Series Max-Duty Synthetic Diesel Oil and a leading conventional 15W-40 diesel oil using the Detroit Diesel* DD13 Scuffing test for specification DFS 93K222.
*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use.


Keeps Turbos Clean

AMSOIL Signature Series Max-Duty Synthetic Diesel Oil provides protection boosted to the max, delivering up to 60% better turbo cleanlinessJ and withstanding the extra demands you place on the turbo when pulling heavy loads or updating the tune for maximum horsepower.

JBased on specification standards of CAT C13 2nd Ring Top Land Carbon testing


Protects Against Rust

Provides up to 2X better rust protection.K Protects Against Rust – Provides up to 2X better rust protection.

KBased on industry standard testing using the NMMA FC-W Rust Test.


VISCOSITY CONTROL

  • Resists oxidation and the thickening effects of soot contamination
  • Retains viscosity after high-temperature service for maximum engine protection and efficiency
  • Provides up to 76 percent less oil consumption5

5Than required by the API CK-4 standard in the Caterpillar-1N oil consumption test


Reduces Oil Consumption

Signature Series Max-Duty Synthetic Diesel Oil provides up to 76% less oil consumption.L

Reduces Oil Consumption – Signature Series Max-Duty Synthetic Diesel Oil provides up to 76% less oil consumption.

LThan required by the API CK-4 standard in the Caterpillar-1N oil consumption test.


EXCELS IN EXTREME TEMPERATURES

  • Provides outstanding protection and performance in hot and cold temperature extremes
  • Resists thermal (heat) breakdown better than conventional and competing synthetic diesel oils.
  • Stays fluid in sub-zero temperatures for easier starting, improved oil flow and reduced wear.

See the Product Data Bulletin for full details.

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

Data Bulletin

SDS

Warranty



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

  • 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
    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.
    Was this review helpful?