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

Product code : DEOQT-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



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

  • 5 star rating
    Luv it
    By  Dave,  a  Verified Buyer  on  August 08, 2022
    Use it in all of our vehicles. Been using it in my diesel trucks for years now and wouldn’t use anything else.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amazing product
    By  SCOTT,  a  Verified Buyer  from  Chevy 3500 Duramax   on  August 04, 2022
    Great product truck running better than ever.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Excellent
    By  ANTHONY,  a  Verified Buyer  from  Maine  on  July 31, 2022
    always fantastic
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    BETTER SAFE THAN SORRY!
    By  RANDY,  a  Verified Buyer  from  Suwanee River  on  July 25, 2022
    I ordered this case for my diesel pickup just in case the rumors that diesel engine oil is soon to be unavailable along with DEF fluid too. Since I recently changed my oil and filter this case will last me well over a year when you consider the extended interval between changes using Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Smooth
    By  MIKE,  a  Verified Buyer  from  NJ   on  July 25, 2022
    I purchased the 5/40 for my 2019 ram 2500 6.7 . The engine runs so much better and cooler . I’m sold I will buy for next oil change
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great Oil
    By  THOMAS,  a  Verified Buyer  from  Durham, NH   on  July 18, 2022
    I have looked up the reviews on the Internet and Amsoil comes out on top for the best in its class. I drive a diesel GMC 2500 and I want the best for my truck. AMSOIL 15W–40 and AMSOIL 5W–40 diesel winter time grade is the very best.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Max duty diesel 15W40
    By  RANDALL,  a  Verified Buyer  from  Indiana  on  July 18, 2022
    Excellent product and fast shipping.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    never going back
    By  ANTHONY,  a  Verified Buyer  from  Maine  on  July 18, 2022
    Have seen tremendous decreases in wear metals in oil analysis, as well as increases in fuel economy vs. the other synthetics I have tried. No need for them anymore.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    great protection
    By  GREGORY,  a  Verified Buyer  from  arkansas  on  July 11, 2022
    will continue to run this oil as long as i have this truck hopefully another 200,000 miles plus.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best out there
    By  DAVID,  a  Verified Buyer  from  Florida   on  July 08, 2022
    Beat oil out there!! Would definitely recommend this product to anyone
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?