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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
  • 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

Warning - Click here for Proposition 65 information for this product

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

Data Bulletin

Warranty

SDS



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

  • 5 star rating
    Oil
    By  CHRIS,  a  Verified Buyer  from  Kaplan   on  December 04, 2023
    All good
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quality oil
    By  PAUL,  a  Verified Buyer  from  Nebraska   on  November 27, 2023
    Very good oil flows great and provides great cold start up protection!! I highly recommend this oil for any diesel owner!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best diesel oil on the market
    By  JEFF,  a  Verified Buyer  from  Central Illinois  on  November 27, 2023
    I have been using Amsoil products for several years. I started them after watching a Gale Banks video on rear differential covers. I got to watching more Banks' videos and he would mention AMSOIL lubricants and how they help with the longevity of the motors and other mechanicals on vehicles because of their superior protection. If it is good enough for Gale Banks and his team, it is great for me.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    F250 , 2015 6.7 Diesel- 200k miles
    By  DAVID,  a  Verified Buyer  from  San Diego   on  November 27, 2023
    Amsoil speaks for itself . The product is bar none compared to any other oil on the market. I’ve used there oil in several different diesel trucks, absolutely love there products!!! With the cost of diesel trucks and labor. Why not run a superior product in your truck ?! UPS is junk- they just drop $300 worth of product off ware ever they want, even with detailed instructions!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The Most Protection
    By  DEREK,  a  Verified Buyer  from  Jacksonville FL   on  November 27, 2023
    I love this oil I use it in everything from my lawn mower to my diesel truck to even my gasoline Chevy and my Buick
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 4 star rating
    Best oil but pricy
    By  DALE,  a  Verified Buyer  from  Jackson, Ohio  on  November 26, 2023
    Works great for my truck. One jug is one oil change. My mechanic highly recommended it.
    Was this review helpful?
  • 5 star rating
    Shippint
    By  CARL,  a  Verified Buyer  from  Vernon  on  November 25, 2023
    Product is great but shipping is getting out of control. It used to be 2 days then it’s 4 my last order was over a week. Get a different shipper or figure it out somehow please this is not good for my customers
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I guess
    By  JOHN,  a  Verified Buyer  from  Iowa  on  November 24, 2023
    The truck is still running. I suppose it's doing it's job.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    oil change
    By  KENNETH,  a  Verified Buyer  from  pa.  on  November 24, 2023
    first oil change with AMSOIL ,dealer would do oil change with AMSOIL , tryed to pull could void warrenty ,doing my self now ,put in FUMOTO valve should make next one ease
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Can't beat Amsoil for diesels
    By  WILLIAM,  a  Verified Buyer  from  Marshall, MI  on  November 19, 2023
    Been using Amsoil signature series in my 22 duramax since I bought her. She loves it!!!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?