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Signature Series 5W-20 Synthetic Motor Oil

Product code : ALMQTC-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.

Signature Series 5W-20 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 5W-20 Synthetic Motor Oil



Signature Series 5W-20 Synthetic Motor Oil

  • 5 star rating
    Best in my opinion
    By  PAO,  a  Verified Buyer  from  Wisconsin   on  July 05, 2022
    Only oil that I have found that helps with gas mileage.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best oil out there
    By  DAVID,  a  Verified Buyer  from  Florida   on  July 05, 2022
    This is the best oil out there!!! My truck runs smoother and much quieter also!!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    HP oil
    By  James,  a  Verified Buyer  from  NY  on  July 03, 2022
    Perfect OEM replacement
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    No more burning
    By  CHARLES,  a  Verified Buyer  from  Luray VA  on  July 03, 2022
    Switched to this in my 14 Outback which used 0w20 and burned a quart every 2000 miles since new. I was running 15w40 but mpg suffered and with the rising price of fuel, went with a zero weight oil. No more burning and better mpg
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil
    By  HOWARD,  a  Verified Buyer  from  66610  on  July 02, 2022
    I have been using Amsoil since 1975 - never had any problems with any of my vehicles.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Recommended by a trusted mechanic
    By  JOHN,  a  Verified Buyer  from  57110  on  July 02, 2022
    Amsoil was highly recommended by a good friend and mechanic. I now use it in my truck car and motor cycle.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Amazing Oil! Use it in nearly everything!
    By  GARRETT,  a  Verified Buyer  from  Missouri  on  June 29, 2022
    Love Amsoil Products, they provide nothing but the best for your engine. No one I trust better after reading their reviews and most impressed by the independent testing they do on all their products. The Signature Series is probably their most tested and proven products, rest assured you are use the best the industry has to offer!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Works great in all our vehicles
    By  RONALD,  a  Verified Buyer  from  South Carolina   on  June 29, 2022
    Helps prevent buildup on intake valves in Cadillac SRX. Nice quiet engines in our 5 Cadillacs 1959-2016, 95 Towncar and 2003 Silverado.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best oil I’ve used. Worth it
    By  CHRIS,  a  Verified Buyer  from  New York  on  June 28, 2022
    Been using this oil in my ‘18 Chevy Malibu since 15k miles and the car now has over 95k and the engine still runs like new. Definitely cheap and worthwhile insurance for anyone looking to maintain their engine for a long time.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    110k and driving
    By  Richard,  a  Verified Buyer  from  Illinois  on  June 28, 2022
    When I bought My 2011 300 3.6 Penstar I immediately switched to Amsoil now with 110k miles she runs like new. I swapped my rocker arms and lifters because of a slight ticking not associated with the fuel injectors, The inside of the motor was clean as a whistle and the one rocker had the slightest of damage barely noticeable. the remaining valvetrain was imaculent. I would recommend this product for your Penstar engines
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?