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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.
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.

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.
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.

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 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 Fights Viscosity Breakdown

AMSOIL fights viscosity breakdown better than the competition,O providing superior protection of pistons, cams and bearings.

Signature Series Fights Viscosity Breakdown – AMSOIL fights viscosity breakdown better than the competition, proving superior protection of pistons, cams and bearings.

OBased upon independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30, Schaeffer’s Supreme 9000 5W-30, Lucas Synthetic 5W-30, Valvoline Conventional Daily Protection 5W-30, Pennzoil 5W-30 and AMSOIL Signature Series 5W-30 in the Kurt Orbahn test. Oils purchased on 05/03/18.


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.


Keeps Engines Clean

  • Formulated with superior thermal durability that resists breakdown and keeps pistons clean.
  • Controls heat and minimizes performance-robbing deposits.
  • Maximizes engine life and performance.

Helps Keep Engines Cleaner

Signature Series is fortified with a heavy treatment of detergent additives, delivering 28 percent more acid-neutralizing power than Mobil 1* and helping engines stay cleaner, longer.LL

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.


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.


Signature Series Cleans

Signature Series has 50% more detergentsD to help keep oil passages clean and promote oil circulation. It 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.

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 Neutralizes Acids

AMSOIL Signature Series is fortified with a heavy treatment of detergent additive and it delivers 30% more acid neutralizing powerE than Mobil 1,* and 36% more than Royal Purple,* helping engines to stay cleaner, longer.

Signature Series Neutralizes Acids – AMSOIL Signature Series is fortified with a heavy treatment of detergent additive and it delivers 30% more acid neutralizing power than Mobil 1, and 36% more than Royal Purple, helping engines to stay cleaner, longer.

EBased upon independent testing of Mobil 1 Annual Protection 5W-30, Royal Purple High Performance 5W-30, Schaeffer’s Supreme 9000 Full Synthetic 5W-30, Royal Purple High Performance 5W-30, Pennzoil 5W-30, Pennzoil Platinum Full Synthetic 5W-30, Valvoline Conventional Daily Protection 5W-30, Valvoline Full Synthetic Modern Engine 5W-30, Lucas Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896. Oils purchased 05/03/18


Signature Series Helps Keep Valves Clean

AMSOIL fights volatilityU 38% better than Mobil 1* and 17% better than Royal Purple,* helping reduce oil consumption and keep valves clean.

Signature Series Helps Keep Valves Clean – AMSOIL fights volatility 38% better than Mobil 1 and 17% better than Royal Purple, helping reduce oil consumption and keep valves clean.

UBased on independent testing of AMSOIL Signature Series Synthetic 5W-20, Mobil 1*Advanced Synthetic 5W-20, Royal Purple* High Performance Synthetic 5W-20, Valvoline* Advanced, Pennzoil Platinum*, Valvoline* High Mileage, Mobil 1* Annual Protection, Schaeffer’s* Supreme 9000, Lucas* Oil, Pennzoil (conventional) and Valvoline* Daily Protection (conventional) in ASTM D5800. Oils purchased October-November 2018.


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.

 


 


Signature Series 0W-40 Synthetic Motor Oil



Signature Series 0W-40 Synthetic Motor Oil

  • 5
    The Best
    By  tex,  a  Verified Buyer  from  Seabrook, Texas  on  January 22, 2022

    Describe the issue

    This oil is no question the BEST!!!!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    FordT350xlt
    By  LANCE,  a  Verified Buyer  from  Port Perry On CA  on  January 22, 2022

    Describe the issue

    New Van with 3.5 eco boost. The First oil change at 7000KM. Lets hope that this oil, over the course of the engine's life proves to be all it is said to be. Oil and filter supply by Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    I believe I've found the best
    By  WILLIAM,  a  Verified Buyer  from  Tampa, FL  on  January 21, 2022

    Describe the issue

    After gathering all information by independent testers, I believe this is the best oil in the market. Love my car, so this is my motor oil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Best oil you can buy and great service
    By  AUREL,  a  Verified Buyer  on  January 21, 2022

    Describe the issue

    Best oil you can buy
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    The absolute best oil on the planet for my 2019 Acura RDX
    By  DAVE,  a  Verified Buyer  from  Wilmington Delaware  on  January 20, 2022

    Describe the issue

    Recently bought a new Acura 2019 RDX needed a top quality oil‘s especially since this thing has close to 300 hp and has a turbo. I believe this oil handles the heat and keeps the engine clean direct injection motors need to be kept clean this oil fits the bill!! Highly recommend it!!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Great oil!!
    By  KEITH,  a  Verified Buyer  on  January 20, 2022

    Describe the issue

    Long-time user with great results!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Best synthetic oil
    By  MARCOS,  a  Verified Buyer  on  January 20, 2022

    Describe the issue

    The first time I used this oil in my car I felt a noticeable difference from the other oil I was using the engine seem to have a little more power.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Very smooth shifting
    By  Ronica,  a  Verified Buyer  from  Georgia  on  January 19, 2022

    Describe the issue

    "CVT" timing transitions seems smoother! Also start up shifting is easier!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Perfect
    By  HENRY,  a  Verified Buyer  on  January 18, 2022

    Describe the issue

    I used amsoil for mitsubishi lancer before so I'll used it again for my subaru. I will recommend this oil for every commuter out there.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Only AMSOIL
    By  KARL,  a  Verified Buyer  from  Sunny Florida  on  January 18, 2022

    Describe the issue

    Have been using for years. I took me a while to break the habit of changing oil every 3,000 miles. Upon the use of AMSOIL products I realized my oil was cleaner and oil changes were further apart due to the great quality of AMSOIL's Synthetic oils. Customer for life
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?