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Signature Series 5W-50 Synthetic Motor Oil

Product code : AMRQT-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.

  • 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.

Signature Series 5W-50 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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Signature Series 5W-50 Synthetic Motor Oil

Data Bulletin

Warranty

SDS



Signature Series 5W-50 Synthetic Motor Oil

  • 5 star rating
    The best oil on the market
    By  ANDY,  a  Verified Buyer  on  September 27, 2023
    Been using this oil since 1995. Did some modifications on my 1998 Camaro and there was no noticeable wear. All the parts looked brand new. I use this in my hot rod and both of my other cars. Simply the BEST
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    5w20
    By  JOHN,  a  Verified Buyer  from  Ohio  on  September 27, 2023
    This is the best oil I’ve ever used,there will be no other oil that is going in my Heritage Softail!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great Synthetic Engine Oil
    By  Smitty,  a  Verified Buyer  from  Sonoma, CA  on  September 26, 2023
    This oil seems to be an elixir for my 115k mile F150 workhorse... she's running smoother than ever (I've run Mobil1 syn since new, until now). Highly recommend for your car or truck too!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    best motor oil in the market for the buck
    By  LUIS,  a  Verified Buyer  from  hidalgo tx   on  September 26, 2023
    very pleased with this oil ffelt the difference on my 2019 ram runs cooler and can feel the engine is quiter now after using this product
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Frustrated that did not get the preferred customer discount
    By  CHRIS,  a  Verified Buyer  from  Loomis Ca  on  September 26, 2023
    Amazing product, the advanced quality can be seen in the YouTube videos that compare Amsoil to other top oils, Amsoil way better after freezing, and heating. Now I want to buy transmission fluid for my cars and oil for 2nd car, and am frustrated I will not get the preferred customer discount for my first purchase.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Liquid Gold
    By  JAMES,  a  Verified Buyer  from  Johnson City Tennessee   on  September 26, 2023
    This is my first time using the oil and filter but I will come back with a answer but one thing I noticed is that it is really quite
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Always performs
    By  GREG,  a  Verified Buyer  on  September 25, 2023
    Good 👍
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Signature Series 5W-30 Synthetic motor oil
    By  Jim,  a  Verified Buyer  from  NE  on  September 25, 2023
    I have found that using this oil has reduced my oil consummation for my 2013 Chevy Avalanche with the 5.3 engine.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    The best
    By  ANGEL,  a  Verified Buyer  from  Reading, Pennsylvania   on  September 24, 2023
    Excellent
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    5W-30 Motor Oil
    By  CHARLES,  a  Verified Buyer  from  FORT PAYNE, AL  on  September 23, 2023
    So far I have only put this in my Ventrac Tractor with 3 cyl Kubota gas engine. Only have 50 hours on so far. Will be putting it in my 2018 Chrysler 300 and my 2012 Jeep Wangler on the next oil changes.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?