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Signature Series 5W-30 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.
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-30 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-30 Synthetic Motor Oil



Signature Series 5W-30 Synthetic Motor Oil

  • 5 star rating
    Big time user of Signature Series 0W-20 Synthetic Motor Oil
    By  David,  a  Verified Buyer  from  CA  on  August 07, 2022
    Use full synthetic on all my Subaru"s. Service is every 6000 miles.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Money that's well spent
    By  JOHN,  a  Verified Buyer  from  Ohio  on  August 05, 2022
    If your asking around about this oil your missing out on the research and Benefits. Dig in and read up you won't be disappointed in the long run.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product
    By  Phang,  a  Verified Buyer  from  Glendale, az  on  August 05, 2022
    This is a great product ! I run this in my '18 F150. I have no issues. It does what it's supposed to do.! I use my truck as a daily driver + hauling 6k lb. Loads on average. I have been using AMSOIL for about 20 years now- I highly recommend it !
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Only the BEST for my Lexus!
    By  AirForceJohn,  a  Verified Buyer  from  Sarasota, FL  on  August 02, 2022
    I personally don't know all the brilliant scientific knowledge that went into a product like this, but I do a lot of research. My conclusion? This is the best motor oil on the market today to help meet my 300,000-mile goal on my 2015 Lexus RX 350. As a great bonus, my RX is averaging over 23 mpg in the city and 27 - 28 mpg on the highway. Way higher than the EPA estimate of 18/25 for this model.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product and Even Better Service
    By  James,  a  Verified Buyer  from  MN  on  August 01, 2022
    I figure if Gail Banks and the people at Motor Trend are using the stuff ya pretty much can't go wrong. I have used Amsoil in the past and have always been happy with it. Went back this time because when 87 octane hit $4 a gallon I shifted to E-50/E-87 and I wanted the quality and extra protection. And talk about service. Received my order the following day. Didn't expect that at all.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product Great Servece
    By  MARTIN,  a  Verified Buyer  from  Vegas  on  August 01, 2022
    Fast Service
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good for 106K miles so Far
    By  DOUG,  a  Verified Buyer  from  Calif.  on  July 31, 2022
    We use this in my college sons 2010 Camry with 106K on it. Was my Wife's before we upgraded her in to a newer car. Been using it since the 1st oil change on the recommendation of my Amsoil Rep. The car has been trouble free engine wise and you all know how hard kids can be on cars. My son has the understanding that there are no replacement cars for him and he needs to take care of it for the rest of college and beyond. This is inexpensive insurance for me. I also run Amsoil synthetic oil in my 20 year old Ford Superduty with 234k on it so far, again take car of your equipment and you will be rewarded with great service from them. I recommend Amsoil Products...
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    very good
    By  REYNALDO,  a  Verified Buyer  from  Tennessee   on  July 30, 2022
    it comes a little under full of the one liter mark
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Hands down best oil
    By  MIKE,  a  Verified Buyer  from  Florida   on  July 30, 2022
    I am constantly running the road for work in Tundra and went from changing my oil every 5k to 10k. Even when I change it after 10k it’s still that fresh brown and never seems to break down like conventional oil. The break down of thi
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Top of the line
    By  DAVID,  a  Verified Buyer  on  July 29, 2022
    I have been using Amsoil since purchasing my SRT8 Challenger in 2010. I did a lot of research & went with the first & the best in the synthetic oil business. I started with the regular full synthetic Amsoil & have been using the signature series for about 4-5 years now. I change my oil once a year regardless of mileage. In HP applications especially, why not put in the best there is.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?