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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
    Over 200,000 and going strong
    By  TIM,  a  Verified Buyer  from  Maryland  on  April 20, 2025
    Use Amsoil products on both high my mileage gas and diesel vehicles.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Signature Series 5W-30 Synthetic Oil
    By  SCOTT,  a  Verified Buyer  from  AZ  on  April 19, 2025
    Ordered another 12 quarts of America’s Best Oil for changes on my Raptor and Bronco. I won’t run anything else, and being a preferred customer bringing the price down, makes it even better!!! No complaints from me whatsoever.
    Was this review helpful?
  • 5 star rating
    Amsoil Signature Series is Top Shelf Product
    By  ROBERT,  a  Verified Buyer  from  Virginia  on  April 19, 2025
    I just switched from Amsoil Euro to Amsoil Signature Series for a 2023 VW Taos. I ran a used oil analysis at that change and the wear metals are 3.7 ppm/1000m. The SUS viscosity is spot on. I have been changing the oil at about 5k miles. I completely trust Amsoil to protect the engine for a long time. That is not an easy job with a small turbo 4-cylinder, DI engine. I am also going to extend my change interval to probably 6500 miles this time and do another used oil analysis. I am going to standardize Amsoil Signature Series on all my vehicles. Not to mention their customer service is great and I get the products quickly. Thank you Amsoil!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Using AmsOil for years
    By  JORDAN,  a  Verified Buyer  on  April 19, 2025
    Hands down best there is!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 4 star rating
    Great oil bad customer service
    By  CARLOS,  a  Verified Buyer  from  Tampa  on  April 18, 2025
    I am really happy with the quality of the signature oil. They are supposed to send me a multi tool for free but never got it. I called customer service and they didn’t resolved the problem.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil
    By  MICHAEL,  a  Verified Buyer  on  April 18, 2025
    Has been working out great for the last 125k miles in my acura. Combined with oil tests change interval of 20k has shown no degradation in protection.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Signature Series is the best oil on the market!!
    By  JEFF,  a  Verified Buyer  from  Fort Erie Ontario Canada  on  April 18, 2025
    I have a 2017 hyundai Santa fe sport with the 2.4 gdi motor. I just had the valve cover gasket changed by my mechanic buddy. With 175000 miles on it he couldn't believe how clean the top end was. No sludge and the camshafts looked like new with no visible wear or discoloration. The car runs like new! He was thoroughly impressed as I was too! Now he is thinking about becoming an Amsoil dealer! I will always use Amsoil products and signature series oil! Keep up the good work!
    Was this review helpful?
  • 5 star rating
    Best on the market
    By  JIM,  a  Verified Buyer  from  Independence Missouri  on  April 17, 2025
    I have run this type of oil and all my vehicles for a very long time one of my vehicles actually hit a half million miles without being rebuilt and was very little issues with sensors and all this type of things it actually helped clean up a car that had bad oil put in it cheap stuff and I had to replace the sensors for once the sensors were replaced I never had to do it again the cleaning agents that this all has is unbelievable and it makes sure car run better and will keep the inside of the motor clean and in a lot of cases it'll actually stop cars from using oil but don't count on that the first time sometimes it takes a couple oil changes before you get all of the old junk out but stay with it it's well worth the money
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great stuff
    By  JASON,  a  Verified Buyer  from  South Carolina   on  April 17, 2025
    The best oil there is IMO. Been using it for years in everything with an engine and have never had any engine failures or problems.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best synthetic oil on the market.
    By  RYAN,  a  Verified Buyer  from  Ny  on  April 17, 2025
    I have been using amazoil for many years. There is nothing else I will put into my vehicles. I have even had it tested by our local cat. Dealer, after being in for a long period in a period of time, it tested better any other oil by far?
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?