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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
    Excellent Products
    By  HAROLD,  a  Verified Buyer  from  Lebanon,TN  on  July 07, 2025
    I have been using Amsoil since 1999. It’s the premier of motor oils. I would only put Amsoil lubricates in my combustible equipment.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Upgrading to AMSOIL
    By  RICK,  a  Verified Buyer  from  Mississippi  on  July 06, 2025
    I read that AMSOIL is the best so I'm going to give it a try in my 35 year old Jeep. The website was easy to use to order what I needed. Thank you for the hat and the stickers!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Short of oil
    By  LARKIN,  a  Verified Buyer  from  VA  on  July 06, 2025
    I ordered a full change for my truck and Harley got shorted 1gallon of oil for my truck called two times said it was on way still have not received it I don’t think I’ll be ordering anymore on line
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    It's an awesome product.
    By  TOM,  a  Verified Buyer  from  Las Vegas NEV.  on  July 06, 2025
    I am a 70 year old man. And believe me, I have had a Few cars. New ones, old ones. You can't imagine how many different types of oil I used before. Until someone told me about Amsoil. At the had a 2007 Hemi Dodge pickup. And started using Amsoil in it Because you know the Hemi Tic... It was gone when I used Amsoil. The product is the best product I've ever used. And we'll keep using it until I pass away.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 4 star rating
    Product Outstanding Shipping Box Horrible
    By  Mike,  a  Verified Buyer  from  South Carolina   on  July 05, 2025
    Outstanding product part of a 18 item purchase including (2) gallon jugs. Shipping box used was horrible. Large box split along (2) of the long seams. Amsoil use a heavier than 32 lb crush box next time.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 4 star rating
    Product Outstanding Shipping Box Horrible
    By  Mike,  a  Verified Buyer  from  South Carolina   on  July 05, 2025
    Outstanding product part of a 18 item purchase including (2) gallon jugs. Shipping box used was horrible. Large box split along (2) of the long seams. Amsoil use a heavier than 32 lb crush box next time.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Favorite product
    By  JAYDEN,  a  Verified Buyer  from  Hummelstown, PA  on  July 05, 2025
    I use this product in my 1995 Suzuki Jimny and it is phenomenal. It still has plenty of life when I change it, the engine has begun to run so much better after switching exclusively to amsoil products. The only non amsoil I use is LiquiMoly CeraTec to coat everything in ceramics to reduce friction. It’s not necessary with Amsoil Signature, but anything to prolong engine life as much as possible!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Trusted
    By  ROBERT,  a  Verified Buyer  from  Staten Island   on  July 05, 2025
    I’ve been using amsoil in all my vehicles for years best of the best just look them up anywhere YouTube social media lmo the best product you can buy
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    The best hands down
    By  AARON,  a  Verified Buyer  on  July 04, 2025
    Still the best money can buy! Keep up the good work my friends.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product. Great Experience
    By  MICHAEL,  a  Verified Buyer  from  Winnipeg  on  July 04, 2025
    This was the second time ordering products direct from Amsoil. Oil and filters arrived quickly and well packed. Exactly what I ordered. Unexpected nice touch was receiving a pair of disposable gloves and paper funnel. I will definitely be ordering again.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?