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AMSOIL Signature Series 0W-40 100% 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 using the ASTM D6891 standard test.
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.

AMSOIL Signature Series 0W-40 100% 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 (Lower = Better)

ASTM D5293 Cold Crank (Lower=Better)

  AMSOIL Signature Series(5W-30) Royal Purple High Performance (5W-30) Lucas (5W-30) Driven LS30 (5W-30) Red Line High Performance (5W-30) Royal Purple HPS (5W-30)
Cranking Viscosity (㎫ ●s) 3800 4500 5000 5750 6100 6100

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

Sequence IVA Engine Test - Lower Number = Less Wear

Sequence IVA Engine Test - Lower Number = Less Wear

  Industry Standard AMSOIL Signature Series 0W-20 Synthetic Motor Oil
Average Cam Wear 90 20.28

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.

Test results from AMSOIL against leading competitor in 100,000-mile test.

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

Piston damage due to an LSPI event observed during the testing of a competitor’s motor oil.

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

Sequence IIIH Engine Test - Lower number = better viscosity control

Sequence IIIH Engine Test - Lower number = better viscosity control

  Industry Standard AMSOIL 1X AMSOIL 2X
Viscosity Increase % 100% 0.1% 49.6%

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

Oil pick-up tube screen showing it's virtually free of 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.

Part from turbocharger.

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

Piston 40% cleaner from using AMSOIL.

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.

 

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AMSOIL Signature Series 0W-40 100% Synthetic Motor Oil

Data Bulletin

Warranty

SDS



AMSOIL Signature Series 0W-40 100% Synthetic Motor Oil

  • 5 star rating
    I have always found AMSOil to be excellent
    By  MICHAEL,  a  Verified Buyer  from  AZ  on  June 11, 2025
    I had a local shop put "synthetic oil" in from a giant barrel. I changed it a mere 1000 miles later with AMSoil and the moment I started the motor it purred... much smoother than mystery oils.
    Was this review helpful?
  • 5 star rating
    Amsoil 5 50
    By  ANGEL,  a  Verified Buyer  from  Odessa Texas  on  June 11, 2025
    Quick shipping, received fast.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil
    By  TOMMY,  a  Verified Buyer  from  New Jersey   on  June 11, 2025
    Been using AMSOIL for over 10 years in my truck,my 69 Camaro and my HD. Great product and company. Short story. Oil for my 69 camaro. They did a quality test. The oil wasn’t up to there specs(has zinc in it for older muscle cars)didn’t have enough. They sent another order of oil free of charge. They didn’t have to say anything. I would have never known. That’s a stand up company. Oil was over $100,that they sent me. customer for life
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Signature Series 0-20W
    By  STEVEN,  a  Verified Buyer  on  June 11, 2025
    Very good product for turbo engines.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    2019 Colorado
    By  OSCAR,  a  Verified Buyer  from  Nakusp, BC Canada  on  June 10, 2025
    I’ve been using amsoil for about 4 years now in my truck and wife’s Jeep and my Harley and I like the fact I only need to change oil once a year. Will continue to do so.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Motor oil
    By  MICHAEL,  a  Verified Buyer  on  June 10, 2025
    Motor seems to be running better. I think it likes this oil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Awesome peoduct
    By  LARRY,  a  Verified Buyer  from  San Jose , CA  on  June 10, 2025
    Here's a sample review: 4.5/5 Stars I've been using amsoil motor oil in my corolla 2013 and 2019 prius prime for a while now, and I'm really impressed with its performance. Both engine runs smoother, and I've noticed a significant reduction in noise and vibration. The oil seems to do a great job of keeping my engine clean, and I've had no issues with leaks or spills.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    6.2 Silverado
    By  LANCE,  a  Verified Buyer  on  June 08, 2025
    I Swap my 6.2 Silverado over to this and it's never run better
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great
    By  ANDREW,  a  Verified Buyer  from  Florida  on  June 07, 2025
    Best oil products
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great Oil
    By  Noah,  a  Verified Buyer  on  June 06, 2025
    Only oil that will go into my 2021 Mustang GT. Amazing product.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?