About this item

• Product Overview
  Compare Motor Oil

  Compare Motor Oil

  

  	Signature Series	Extended-Life (XL)	High-Mileage	Hybrid	OE
  Wear Protection
  Engine Cleanliness
  Service Interval
  Extreme Temp Performance
  Corrosion Protection
  Oil-Consumption Control
  Viscosity Control
  Leak Protection
  Severe-Service Protection

  View Full Image

  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)

  

  	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

  

  	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.

  

  ^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

  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

  

  	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 detergents^D 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

  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 required^C by the GM dexos1* Gen 2 specification.

  ^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

  ^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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• Technical Specifications
  Data Bulletin

  Data Bulletins

  Warranty

  WARRANTY

  SDS

  SDS

  
  
  
• Product Reviews
  5 star rating

  Based on 6,997 reviews

  Based on 6,997 reviews

  See all customer reviews

  Sort by

  Most Recent Most Helpful Highest Rating Lowest Rating Oldest

  • 5 star rating
    Quality
    By  REMI,  a  Verified Buyer  from  Odessa tx.  on  July 27, 2026

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    Very good product quality.
    Bottom Line

    Yes, I would recommend this to a friend.
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  • 5 star rating
    High Quality Oil
    By  VICTOR,  a  Verified Buyer  from  Las Cruces Nm  on  July 27, 2026

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    ⭐⭐⭐⭐⭐ Excellent products! The AMSOIL engine oil keeps my engine running smooth and quiet, and the oil filter is high quality and provides great protection. I’ve had a great experience with both and highly recommend them.
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

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  • 5 star rating
    Best Motor Oil Ever
    By  JAMES,  a  Verified Buyer  from  Orlando  on  July 27, 2026

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    Ordered and picked up the same day - could have had it delivered but i was in a hurry. I use it in all my cars and trucks for the last 15 years and I never have to worry about my engines.
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)
  • 5 star rating
    civic si
    By  ADRIAN,  a  Verified Buyer  on  July 26, 2026

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    Just the right amount of oil I need for the vehicle
    Bottom Line

    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best product to protect your investment
    By  DAVID,  a  Verified Buyer  from  Chicora PA  on  July 26, 2026

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    Best product to protect your investment In the long haul HANDS DOWN!
    Bottom Line

    Yes, I would recommend this to a friend.
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  • 5 star rating
    5 30 synthetic
    By  BARRY,  a  Verified Buyer  from  Hazletownship Pennsylvania   on  July 26, 2026

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    Great product and great Customer service
    Bottom Line

    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quality product
    By  PHIL,  a  Verified Buyer  from  Lockport   on  July 26, 2026

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    I run 5w30 signature series in my 2021 F-150 3.5 Eco Boost engine. This engine has twin turbos and they run extremely hot. I feel Amsoil gives the protection needed to reduce engine and turbo wear. Phil
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

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  • 5 star rating
    Amsoil is the best there is
    By  FRANK,  a  Verified Buyer  from  Asheville NC  on  July 25, 2026

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    I have been using Amsoil in my Subarus for over a 15 yrs. I usually run 18-20k filter every 5k before changing. I have never had any issues ever. Best there is
    Bottom Line

    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good value and convenient
    By  MICHAEL,  a  Verified Buyer  from  Kansas  on  July 25, 2026

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    The large oil jug is a convenient size and bit more economical. I will only use Amsoil in my high meager Tundra
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

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  • 5 star rating
    Best on the planet
    By  JONATHAN,  a  Verified Buyer  from  Oak Point Texas  on  July 24, 2026

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    Always use Amsoil. Especially with many vehicles
    Bottom Line

    Yes, I would recommend this to a friend.
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• Highlights

  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.

• Returns

  We offer easy returns for customers. If your product is unused and unopened, you may return it within 30 days for a full refund of the purchase price. View full AMSOIL Return Policy.

• Payments

  We accept Visa, Mastercard, American Express, Discover and PayPal, and provide secure checkout and encrypted payment processing.

• Product Overview
  Compare Motor Oil

  Compare Motor Oil

  

  	Signature Series	Extended-Life (XL)	High-Mileage	Hybrid	OE
  Wear Protection
  Engine Cleanliness
  Service Interval
  Extreme Temp Performance
  Corrosion Protection
  Oil-Consumption Control
  Viscosity Control
  Leak Protection
  Severe-Service Protection

  View Full Image

  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)

  

  	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

  

  	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.

  

  ^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

  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

  

  	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 detergents^D 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

  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 required^C by the GM dexos1* Gen 2 specification.

  ^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

  ^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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• Technical Specifications
  Data Bulletin

  Data Bulletins

  Warranty

  WARRANTY

  SDS

  SDS

  
  
  
• Product Reviews
  5 star rating

  Based on 6,997 reviews

  Based on 6,997 reviews

  See all customer reviews

  Sort by

  Most Recent Most Helpful Highest Rating Lowest Rating Oldest

  • 5 star rating
    Quality
    By  REMI,  a  Verified Buyer  from  Odessa tx.  on  July 27, 2026

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    Very good product quality.
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)
  • 5 star rating
    High Quality Oil
    By  VICTOR,  a  Verified Buyer  from  Las Cruces Nm  on  July 27, 2026

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    ⭐⭐⭐⭐⭐ Excellent products! The AMSOIL engine oil keeps my engine running smooth and quiet, and the oil filter is high quality and provides great protection. I’ve had a great experience with both and highly recommend them.
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)
  • 5 star rating
    Best Motor Oil Ever
    By  JAMES,  a  Verified Buyer  from  Orlando  on  July 27, 2026

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    Describe the issue

    Failed to verify captcha

    Cancel Submit
    Ordered and picked up the same day - could have had it delivered but i was in a hurry. I use it in all my cars and trucks for the last 15 years and I never have to worry about my engines.
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)
  • 5 star rating
    civic si
    By  ADRIAN,  a  Verified Buyer  on  July 26, 2026

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    Just the right amount of oil I need for the vehicle
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)
  • 5 star rating
    Best product to protect your investment
    By  DAVID,  a  Verified Buyer  from  Chicora PA  on  July 26, 2026

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    Best product to protect your investment In the long haul HANDS DOWN!
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)
  • 5 star rating
    5 30 synthetic
    By  BARRY,  a  Verified Buyer  from  Hazletownship Pennsylvania   on  July 26, 2026

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    Great product and great Customer service
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)
  • 5 star rating
    Quality product
    By  PHIL,  a  Verified Buyer  from  Lockport   on  July 26, 2026

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    I run 5w30 signature series in my 2021 F-150 3.5 Eco Boost engine. This engine has twin turbos and they run extremely hot. I feel Amsoil gives the protection needed to reduce engine and turbo wear. Phil
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)
  • 5 star rating
    Amsoil is the best there is
    By  FRANK,  a  Verified Buyer  from  Asheville NC  on  July 25, 2026

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    I have been using Amsoil in my Subarus for over a 15 yrs. I usually run 18-20k filter every 5k before changing. I have never had any issues ever. Best there is
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)
  • 5 star rating
    Good value and convenient
    By  MICHAEL,  a  Verified Buyer  from  Kansas  on  July 25, 2026

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    Describe the issue

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    The large oil jug is a convenient size and bit more economical. I will only use Amsoil in my high meager Tundra
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)
  • 5 star rating
    Best on the planet
    By  JONATHAN,  a  Verified Buyer  from  Oak Point Texas  on  July 24, 2026

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    Always use Amsoil. Especially with many vehicles
    Bottom Line

    Yes, I would recommend this to a friend.
    Was this review helpful?

    YES (0) NO (0)