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AMSOIL Signature Series 5W-20 100% 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.
  • 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, 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.
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 5W-20 100% 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 5W-20 100% Synthetic Motor Oil

Data Bulletin

Warranty

SDS



AMSOIL Signature Series 5W-20 100% Synthetic Motor Oil

  • 5 star rating
    Amsoil Signature Series Oil
    By  TONY,  a  Verified Buyer  from  Lancaster,PA  on  February 27, 2024
    Been using Amsoil for years now. Always an easy experience, fast delivery and a good feeling knowing the quality and reputation of using Amsoil products. Would highly recommend to anyone.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best oil ever
    By  MACIEJ,  a  Verified Buyer  from  Wisconsin   on  February 27, 2024
    I’m using this oil for my STI and Lexus ls430 . I have over 200000 miles on Lexus no oil added between oil changes.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best oil I ever used .
    By  MACIEJ,  a  Verified Buyer  from  Wisconsin   on  February 27, 2024
    I’m using this oil for my new Subaru.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Doesn't disappoint..
    By  RICHARD,  a  Verified Buyer  on  February 26, 2024
    Best available oil I believe
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Doesn't disappoint..
    By  RICHARD,  a  Verified Buyer  on  February 26, 2024
    Best available oil
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Summer Oil
    By  FRITZ,  a  Verified Buyer  from  North Dakota  on  February 26, 2024
    I run this in the summer in my '23 WRX. The 5w-30 offers better high temp protection than the 0w-20 I run in the winter months.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Perfect OEM Replacement
    By  FRITZ,  a  Verified Buyer  from  North Dakota  on  February 26, 2024
    I use this in the winter in my '23 WRX. It's an excellent replacement for the OEM oil and far exceeds it as well. Superior protection and cold temp flow is extremely important up here where temps can run in the negatives frequently.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Good product
    By  JOSE,  a  Verified Buyer  from  Florida   on  February 26, 2024
    Fast way to explain just a great oil
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Only The Best
    By  MICHAEL,  a  Verified Buyer  from  High Point, NC  on  February 24, 2024
    First, I've been a diehard Mobil 1 user for umpteen years and I have nothing bad to say about them. I bought a used Jeep and I travel for work. I've heard about AMSOIL, but never thought much about them until I bought the Jeep. I got on their website and started reading. They have copious amounts of data AND they compared against MOBIL 1, so THAT says something. The data shows AMSOIL is the better choice so I made the switch. I CANNOT attest to any improvement in the change. I am writing this review about having piece-of-mind lubricating my vehicles components. Since I have to drive almost 200 miles round trip per day for work, I don't have time for second best. Is AMSOIL more expensive? YES, but it's a "pay now or pay later" thing with me. I'll pay the extra for a data-proven product and piece-of-mind.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product
    By  TOM,  a  Verified Buyer  from  mapleton  on  February 24, 2024
    Best oil on the market. My mechanic is a Ford guru who is big in the racing scene in Utah and that is all he will use.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?