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AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil

Product code : ASLQT-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 5W-30 100% 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-30 100% Synthetic Motor Oil

Data Bulletin

Warranty

SDS



AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil

  • 5 star rating
    Best Synthetic Oil
    By  NAMAN,  a  Verified Buyer  from  Brampton  on  May 10, 2025
    This is the best engine oil I have ever used for my Dodge Challenger. Thanks!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    like it
    By  KEVIN,  a  Verified Buyer  from  PA   on  May 10, 2025
    First time using the Signature Series 5W-30 and I like it so far 2014 Ford Taurus SHO
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    16 year old Lexus engine sounds quiet and smooth
    By  ALFREDO,  a  Verified Buyer  from  Austin, Tx  on  May 08, 2025
    16 year old Lexus engine sounds quiet and runs smoothly 👍🏼
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Good Stuff
    By  MATTHEW,  a  Verified Buyer  on  May 08, 2025
    Truck runs better than ever
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product
    By  THOMAS,  a  Verified Buyer  from  Barstow ca. 92312  on  May 08, 2025
    Products are top notch and customer service excellent and shipping is fast and dependable.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Motor has less chatty/ increased fuel mileage (see review)
    By  BRYAN,  a  Verified Buyer  on  May 07, 2025
    I put this in my 2021 Toyota tundra 1794, as well as aired the Goodyear wrangler (stock size) tires up to 47# rear and 50# in the front, followed by unplugging the negative side of the battery overnight. After I hooked the negative back up, I drove several trips using the sport mode(as soon as I put it in gear I bumped it up to 6th gear and left it. This allowed the motor to not rev up when slowing down. After a week of driving this way I went back to d and not sport mode. Result= the truck went from a steady 12 mpg or lower up to a steady high 15 mpg up through so far 19.+ on state route easier driving. (Looking ahead to let off the pedal at times coasting made more since to stop) avoid cruise because it uses the engine to slow the truck down so it waste fuel mileage.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Excellent
    By  JAMES,  a  Verified Buyer  from  Pa  on  May 06, 2025
    Use amsoil in everything I own. One car with 5W-30 has over 370,000 miles, going strong.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product
    By  Vette z o six,  a  Verified Buyer  from  Wa  on  May 06, 2025
    Great stuff, it's expensive but I'm gonna buy it anyway.... 🤣
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    So far so good
    By  SCOTTk,  a  Verified Buyer  from  Ny  on  May 05, 2025
    Seems to keep the engine quite clean. No issues running 91 on a 2.7 T
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Only 0w40 oil
    By  DENNIS,  a  Verified Buyer  from  Alabama   on  May 05, 2025
    Only oil I trust , to hold up to it's viscosity, wonder what's stronger, this, zrod or the dominator racing oil
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?