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

Product code : DEOQTC-EA

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

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

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

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

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



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.

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

SDS

Data Bulletin

Warranty



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

  • 5 star rating
    Best oil you can buy.
    By  JOHN,  a  Verified Buyer  from  Long Island NY  on  November 28, 2022
    Anything Ams is too quality top notch beats everyone else. If you don't believe me get an couple old pans and an OUTDOOR camp stove. Put AMS against anything else and I garantee it will shock you. Be careful. I simply won't put anything else in my vehicles or toys.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature Series provides a noticeable difference
    By  AUSTIN,  a  Verified Buyer  on  November 27, 2022
    I have used other brands’ cheaper full synthetic engine oils in the past, but after switching to Signature Series oil in my ‘97 12v, I have noticed quieter and smoother engine operation from the oil change alone. My truck is going on 400k miles, and it’s safe to say it will the Signature Series treatment going forward.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Amsoil synthetic oil
    By  DWAYNE,  a  Verified Buyer  from  Terrace BC  on  November 25, 2022
    I broke my 2003 duramax in and switched to Amsoil 15-40 and now have over 800,000kms on it with out ever removing the valve covers and it is still running strong
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Signature series max duty
    By  SHANE,  a  Verified Buyer  on  November 22, 2022
    I have a lifted 2014 ram 2500. since I start using amsoil it runs smoother and quieter for longer. I 100% recommend them
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    2011 GMC SIERRA 3500HD Diesel oil change
    By  TONY,  a  Verified Buyer  from  Arizona  on  November 21, 2022
    Ordering from AMSOIL is always super fast shipping and the best quality of oil out there. I run it in all my Vehicles which is including my 18 turbo RZR and my built Harley.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Diesel oil
    By  JAMES,  a  Verified Buyer  from  Pa  on  November 13, 2022
    Been running this oil from new purchase 2016 of truck
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Beat oil out there
    By  DAVID,  a  Verified Buyer  from  Florida  on  November 06, 2022
    This is the best oil out there! I won’t use anything but amsoil product in my truck and car
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Good quality oil
    By  DOUGLAS,  a  Verified Buyer  from  North Texas  on  November 01, 2022
    I like Amsoil's quality and their constant testing.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil
    By  PAUL,  a  Verified Buyer  on  October 31, 2022
    We go 8000 mi. Between oil change now
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil, and it was in stock
    By  CHRIS,  a  Verified Buyer  on  October 27, 2022
    Like the title says great oil, and it was in stock when I ordered it, and arrived with in a week of ordering. Planned on changing to Amsoil, and when the stores supply of the other brand I had used I changed.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?