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Signature Series 0W-40 Synthetic Motor Oil

Product code : AZFQT-EA

A New Level of Motor Oil Technology

  • 75% more engine protection against horsepower loss and wear.1
  • 50% more cleaning power vs. AMSOIL OE Motor Oil
  • Protects turbochargers 72% better than required2 by the GM dexos1 Gen 2 specification.
  • 28% more acid-neutralizing power than Mobil 1.3
  • Trusted by professional engine builders
  • Guaranteed protection for up to 25,000 miles or 1 year

1Based on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.
2Based on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
3Based upon independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896. Oils purchased in July 2020.

  • 75% more engine protection against horsepower loss and wear.1
  • 50% more cleaning power vs. AMSOIL OE Motor Oil
  • Protects turbochargers 72% better than required2 by the GM dexos1 Gen 2 specification.
  • 28% more acid-neutralizing power than Mobil 1.3
  • Trusted by professional engine builders
  • Guaranteed protection for up to 25,000 miles or 1 year

1Based on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.
2Based on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
3Based upon independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896. Oils purchased in July 2020.

Warning - Click here for Proposition 65 information for this product

Signature Series 0W-40 Synthetic Motor Oil



Engineered for enthusiasts seeking maximum protection and performance. Precision-formulated with cutting-edge technology and a longstanding devotion to making the world’s best motor oil. The result: engine protection that blows the doors off the highest industry standards.

See the Product Data Bulletin for full details.

Fights Engine Wear

  • 75 percent more engine protection against horsepower loss and wear1 than required by the industry standard, extending the life of vital components like pistons and cams.
  • Develops a strong fluid film that keeps metal surfaces separated.
  • Robust anti-wear additives further reduce wear in metal-to-metal contact regions for maximum engine life.

1Based on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.


Signature Series Improves Startup Protection

AMSOIL provides better cold cranking viscosity, helping improve wear protection for engine components at startup.PP

ASTM D5293 Cold Crank Simulator test

PPBased on independent third-party testing in the industry-standard ASTM D5293 Cold Crank Simulator test as required by SAE J300.
*Trademark 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.


Signature Series Fights Wear

75% more engine protection against horsepower loss and wear.A

Signature Series Fights Wear – 75% more engine protection against horsepower loss and wear.

ABased on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.


Signature Series Delivers Powerful Protection

AMSOIL delivers powerful protection. How good is it? An independent lab compared AMSOIL synthetic motor oil head-to-head against a leading competitor in a 100,000-mile test.P AMSOIL provided far superior wear protection and kept bearings looking like new.

Signature Series Delivers Powerful Protection – AMSOIL delivers powerful protection.  How good is it?  An independent lab compared AMSOIL synthetic motor oil head-t-head against a leading competitor in a 100,000-mile test.  AMSOIL provided far superior wear protection and kept bearings looking like new.

PTesting conducted in an independent lab using AMSOIL Signature Series 5W-30 Synthetic Motor Oil and a leading synthetic-blend 5W-30 motor oil in Ford F-150 trucks with 3.5L twin-turbo engines.


Signature Series Protects Against LSPI

AMSOIL Synthetic Motor Oils achieved 100% protection against LSPI.B

Signature Series protects Against LSPI – AMSOIL Synthetic Motor oil achieved 100% protection against LSPI.

Example of piston damage due to an LSPI event observed during the testing of a competitor’s motor oil. The red arrows indicate sections of the ring land that have broken away from the piston.

BBased on zero LSPI events in five consecutive tests of AMSOIL Signature Series, XL and OE 5W-30 Motor Oil in the LSPI engine test required by the GM dexos1 Gen 2 specification.


Signature Series Resists Viscosity Increase

Signature Series is barely challenged by the industry-standard testing, demonstrating only a 0.1% viscosity increase. Even when the test length is doubled, AMSOIL delivered twice the viscosity control required by the standard.GG

Signature Series resists viscosity increase – in industry-standard testing, it demonstrated only 0.1% viscosity increase.

GGBased on independent testing of AMSOIL Signature Series 5W-30 in the Sequence IIIH Engine Test (ASTM D8111), required by the ILSAC GF-6 and API SP specifications.


Signature Series Helps Keep Engines Cleaner

  • Fortified with a heavy treatment of detergent additives, delivering 28% more acid-neutralizing power than Mobil 1* and helping engines stay cleaner, longer.LL
  • 50% more detergentsD to help keep oil passages clean and promote oil circulation.
  • Controls heat and minimizes performance-robbing deposits.
  • Superior thermal durability that resists breakdown and keeps pistons clean.
  • Provides 90% better protection against sludge.DD
Signature Series Cleans – AMSOIL Signature Series Synthetic Motor Oil has 50% more detergents to help keep oil passages clean and promote oil circulation.  It provides 90% better protection against sludge.

The oil pick-up tube screen is virtually free of sludge.

LLBased upon independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896. Oils purchased July 2020.

Dvs. AMSOIL OE Motor Oil

DDBased on independent testing of AMSOIL Signature Series 5W-30 in the ASTM D6593 engine test for oil screen plugging as required by the API SN specification.


Signature Series Guards Turbos

Protects turbochargers 72% better than requiredC by the GM dexos1* Gen 2 specification.

Signature Series Guards Turbos – Protects turbochargers 72% better than required by the GM dexos1 Gen 2 specification.

CBased on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.


Keeps Pistons Cleaner

Even after doubling the length of the industry-standard test, AMSOIL delivered 40% cleaner pistons than required by the standard.FF

AMSOIL Keeps Pistons Cleaner – Even after doubling the length of the industry-standard test.  AMSOIL delivered 40% cleaner pistons than required by the standard.

FFBased on independent testing of AMSOIL Signature Series 5W-30 in the Sequence IIIH Engine Test (ASTM D8111), required by the ILSAC GF-6 and API SP specifications.


Trusted by Professionals

Dedicated engine builders and mechanics put in long hours honing their craft. These architects of powerful, high-performance engines turn to Signature Series to protect their passion.

Hear what they have to say.

Barry Robotnick Testimonial


Wistia video thumbnail


Signature Series 0W-40 Synthetic Motor Oil

SDS

Data Bulletin

Warranty



Signature Series 0W-40 Synthetic Motor Oil

  • 5 star rating
    Best oil on the market
    By  GARY,  a  Verified Buyer  from  California   on  December 07, 2022
    Engine run’s better. Better gas mileage. Change oil every 12 months or 25,000 miles. Totally worth it.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Amsoil Signature Series Oil
    By  JEFF,  a  Verified Buyer  on  December 07, 2022
    Amsoil is the best motor oil I have found. Not only in products but the best company overall. I’ve used just about all of their products and the results speak for themselves. I’m always amazed and that’s why I only use Amsoil exclusively in what ever I own. Awesome company!!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    0w-20
    By  MARK,  a  Verified Buyer  on  December 07, 2022
    aok
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best oil
    By  FREEMAN,  a  Verified Buyer  from  OHIO   on  December 06, 2022
    Been using Amsoil for years. Wouldn’t change for anything
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best oil out there
    By  SCOTT,  a  Verified Buyer  from  Indiana   on  December 06, 2022
    I love Amsoil it’s the best oil you can buy! Note that I’ve started with them I’ll never use another oil again!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Sig. Series
    By  RICHARD,  a  Verified Buyer  from  Stl. MO  on  December 04, 2022
    Change once a year. Never an issue.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product
    By  BRIAN,  a  Verified Buyer  from  Queens,NY  on  December 04, 2022
    I used to use a different brand of oil until my neighbor told me about Amsoil and that’s all I use for all of my vehicles.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Power Wagon 6.4L Hemi
    By  ANDREW,  a  Verified Buyer  from  Ontario  on  December 04, 2022
    Started running AmsOil signature in my 6.4, could immediately tell the engine sounded much smoother. Wish I started running it sooner!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Outstanding Oil
    By  NATHAN,  a  Verified Buyer  from  Wisconsin   on  December 04, 2022
    We run this in our commercial mowers and with many mowers well over 2,000 hours on the meter still running like new!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    The beat oil money can buy. Plenty of tests on youtube..
    By  CAM,  a  Verified Buyer  from  colorado  on  December 03, 2022
    well tested, no need for additional seafoam or other detergents. I used to be a royal purple customer, but this oil is proven to take care of your high end motors.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?