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Signature Series 5W-20 Synthetic Motor Oil

Product code : ALMQT-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
    Top of the Line Engine Oil for Many Vehicles
    By  ERIC,  a  Verified Buyer  from  Oakland, California  on  August 15, 2022
    Never fails to protect my engines for at least 5,000 mile intervals. You can even extend the oil filter change to 15,000 miles due to the great detergent capabilities of the Signature Series Oil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Any oil
    By  KEVIN,  a  Verified Buyer  on  August 13, 2022
    Amsoil seems to be the best oil that I’ve used in any circumstance. Either racing or every day use it’s an awesome product.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great Oil
    By  Landon,  a  Verified Buyer  from  Brunswick, GA  on  August 11, 2022
    Engine looks great and clean inside due to this oil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    AWESOME OIL!!!!
    By  Carey,  a  Verified Buyer  from  NV  on  August 11, 2022
    What can you say best oil made! not many oils come close to it just use it!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Now that’s great motor oil
    By  BRYAN,  a  Verified Buyer  from  Floy  on  August 11, 2022
    Im using the 10-30 in my Dodge Ram since coming off the show room floor in 2004 .3.7 liter motor 1 million 369 thousand miles later shes still rolling down the road like a champ and no smoke or oil burning . I just bought a new jeep let’s see how it holds up . . The soil is excellent so I’ll be sticking with it from now until eternity excellent motor oil do use in any vehicle Bryan
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 4 star rating
    Good motor oil
    By  MARUISZ,  a  Verified Buyer  from  Hagersville   on  August 10, 2022
    Very good motor oil. Have been using Amsoil for over 15 years. I use it in my off-road vehicles, my truck, suv and lawn equipment. I change my signature Amsoil at 15,000 kms, well before it’s time, but I prefer more often oil changes. I would give it 5 stars if price was lower. Otherwise, two thumbs up for this great product.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Excellent oil.👍🏼
    By  TIMOTHY,  a  Verified Buyer  from  Atascadero   on  August 10, 2022
    I have bought Amsoil for a number of years now for our Jeep Grand Cherokee Laredo four-wheel-drive. I also use it in my Harley Davidson motorcycle. I would recommend this product.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    First oil change
    By  PHILIP,  a  Verified Buyer  from  Hudson Valley New York   on  August 09, 2022
    My new Ram 2500 just had its first oil change at 4600 miles. So I did my research and chose AMSOIL for my oil change. For now I used OEM filter but, next time I will use AMZOIL filter for sure in order to get fullest use of oil and filter past 12,000 miles. I plan on using my truck for pleasure and commercial use. Regardless, I need dependability and upmost best from this product. So I will keep in touch and let you know as the miles get pit on. Thanks and ttyl.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent product!!
    By  KYLE,  a  Verified Buyer  from  Phillipsburg NJ  on  August 08, 2022
    Both of my vehicles use 5w20 and I started using amsoil about a year ago, I'll never go back. Both of the engines sound and run great! An it's a peace of mind I'm protecting my investments! Noticed more MPG also!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Signature Series 0W-30 Synthetic Motor Oil
    By  James,  a  Verified Buyer  from  IL  on  August 08, 2022
    It quieted down my motor a bit and it runs smoother
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?