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

  Custom-Built to Outperform

  AMSOIL Signature Series 100% Synthetic Motor Oil is formulated for drivers who demand the absolute best engine protection. Built with advanced synthetic base oils and a precision-engineered additive system, it is designed to control wear, resist volatility and maintain viscosity under extreme heat, pressure and cold-start conditions. The result is uncompromising film strength, cleaner components and protection that pushes beyond industry standards into a class of its own.
  
  Modern engines place unprecedented stress on motor oil through turbocharging, direct injection, higher temperatures and extended service intervals. Signature Series is engineered to meet those challenges head on, delivering more protection, performance and confidence mile after mile, even during extreme use.

  See the Product Data Bulletin for full details.

  2X BETTER Protection Against Volatility

  AMSOIL Signature Series delivers 2X better protection against volatility,³ helping reduce oil consumption, minimize top-offs and keep engines cleaner over time.

  
  
  

  ³Based on AMSOIL Signature Series 0W-20 100% Synthetic Motor Oil compared to the API SQ limit using the ASTM D5800 Noack volatility test.

  Guards Against

  Low-speed pre-ignition (LSPI) remains a serious concern in today’s turbocharged, direct-injection engines, where uncontrolled combustion events can damage pistons and other critical components, especially as motor oil ages. AMSOIL Signature Series 100% Synthetic Motor Oil is engineered to help prevent LSPI by maintaining a strong, stable formulation that continues to deliver outstanding performance throughout the drain interval. Even after 25,000 miles of use, Signature Series delivers 4X more piston protection against LSPI⁴ than the industry standard requires.

  ⁴Using AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil following a 25,000-mile service interval in the Sequence IX aged-oil LSPI test.

  Preserves Horsepower and Torque

  AMSOIL Signature Series 100% Synthetic Motor Oil is built to help engines run stronger, longer⁵ – helping to protect engines from performance loss throughout their life.

  

  ⁵Using Signature Series 100% Synthetic 5W-30 Motor Oil in a 2025 Ford F-150 Raptor in a 125K-mile accumulation study. Based on comparative start- and end-of-test horsepower and torque.

  Proven Cleaning Power

  In Sequence IIIH testing, AMSOIL Signature Series delivers 72% more protection against piston deposits than required by industry standards,⁶ helping ensure cleaner pistons and consistent performance over time.

  

  ⁶Based on AMSOIL Signature Series 5W-30 in the Sequence IIIH Test.

  Even after doubling the length of the Sequence IIIH test, Signature Series provided 31% better protection than required,⁷ demonstrating its ability to maintain cleanliness far beyond industry standards.

  

  ⁷Based on AMSOIL Signature Series 5W-30 in a double-length Sequence IIIH test.

  No Sludge, Just Protection

  During a 125K-mile accumulation study on a 2025 Ford F-150 Raptor, the engine experienced 0% oil screen plugging.⁸

  

  ⁸As demonstrated in a 125K-mile accumulation study on a 2025 Ford F-150 Raptor which had 0% plugging.

• Technical Specifications
  Performance Studies

  Las Vegas Taxi Cab Field Study

  Data Bulletin

  Data Bulletins

  Warranty

  WARRANTY

  SDS

  SDS

  
  
  
• Product Reviews
  5 star rating

  Based on 6,994 reviews

  Based on 6,994 reviews

  See all customer reviews

  Sort by

  Most Recent Most Helpful Highest Rating Lowest Rating Oldest

  • 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?

    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.
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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.
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    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.
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  • 5 star rating
    Great
    By  CHRIS,  a  Verified Buyer  from  Plymouth   on  July 24, 2026

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    Great product would recommend it to everyone
    Bottom Line

    Yes, I would recommend this to a friend.
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  • 5 star rating
    So far the oil is doing what oil should,
    By  GALE,  a  Verified Buyer  from  Grand Junction, Colorado   on  July 24, 2026

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    I have a high flow oil pump installed in my motor, oil pressure runs mid 50 psi and consumption hasn't been a problem yet. I believe amsoil is the result of the steabyness i was looking for.
    Bottom Line

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

    YES (0) NO (0)
  • 5 star rating
    Oil and wix xp filter
    By  ANTHONY,  a  Verified Buyer  from  Rockford Illinois   on  July 23, 2026

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    Love the oil not so much the filter.I really wish you guys would get the amsoil ea17 filter back in stock, its been far to long they've been on back order.
    Bottom Line

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

  A New Level of Motor Oil Technology

  • Protects – Ultimate long-life anti-wear protection
  • Cleans – Fights sludge and carbon buildup¹
  • Adapts – Responds to changing conditions
  • Performs – Proven beyond the standard²

  
  

  ¹Based on Sequence VH and IIIH tests.
  ²Based on double-length Sequence IIIH test.

• 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

  Custom-Built to Outperform

  AMSOIL Signature Series 100% Synthetic Motor Oil is formulated for drivers who demand the absolute best engine protection. Built with advanced synthetic base oils and a precision-engineered additive system, it is designed to control wear, resist volatility and maintain viscosity under extreme heat, pressure and cold-start conditions. The result is uncompromising film strength, cleaner components and protection that pushes beyond industry standards into a class of its own.
  
  Modern engines place unprecedented stress on motor oil through turbocharging, direct injection, higher temperatures and extended service intervals. Signature Series is engineered to meet those challenges head on, delivering more protection, performance and confidence mile after mile, even during extreme use.

  See the Product Data Bulletin for full details.

  2X BETTER Protection Against Volatility

  AMSOIL Signature Series delivers 2X better protection against volatility,³ helping reduce oil consumption, minimize top-offs and keep engines cleaner over time.

  
  
  

  ³Based on AMSOIL Signature Series 0W-20 100% Synthetic Motor Oil compared to the API SQ limit using the ASTM D5800 Noack volatility test.

  Guards Against

  Low-speed pre-ignition (LSPI) remains a serious concern in today’s turbocharged, direct-injection engines, where uncontrolled combustion events can damage pistons and other critical components, especially as motor oil ages. AMSOIL Signature Series 100% Synthetic Motor Oil is engineered to help prevent LSPI by maintaining a strong, stable formulation that continues to deliver outstanding performance throughout the drain interval. Even after 25,000 miles of use, Signature Series delivers 4X more piston protection against LSPI⁴ than the industry standard requires.

  ⁴Using AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil following a 25,000-mile service interval in the Sequence IX aged-oil LSPI test.

  Preserves Horsepower and Torque

  AMSOIL Signature Series 100% Synthetic Motor Oil is built to help engines run stronger, longer⁵ – helping to protect engines from performance loss throughout their life.

  

  ⁵Using Signature Series 100% Synthetic 5W-30 Motor Oil in a 2025 Ford F-150 Raptor in a 125K-mile accumulation study. Based on comparative start- and end-of-test horsepower and torque.

  Proven Cleaning Power

  In Sequence IIIH testing, AMSOIL Signature Series delivers 72% more protection against piston deposits than required by industry standards,⁶ helping ensure cleaner pistons and consistent performance over time.

  

  ⁶Based on AMSOIL Signature Series 5W-30 in the Sequence IIIH Test.

  Even after doubling the length of the Sequence IIIH test, Signature Series provided 31% better protection than required,⁷ demonstrating its ability to maintain cleanliness far beyond industry standards.

  

  ⁷Based on AMSOIL Signature Series 5W-30 in a double-length Sequence IIIH test.

  No Sludge, Just Protection

  During a 125K-mile accumulation study on a 2025 Ford F-150 Raptor, the engine experienced 0% oil screen plugging.⁸

  

  ⁸As demonstrated in a 125K-mile accumulation study on a 2025 Ford F-150 Raptor which had 0% plugging.

• Technical Specifications
  Performance Studies

  Las Vegas Taxi Cab Field Study

  Data Bulletin

  Data Bulletins

  Warranty

  WARRANTY

  SDS

  SDS

  
  
  
• Product Reviews
  5 star rating

  Based on 6,994 reviews

  Based on 6,994 reviews

  See all customer reviews

  Sort by

  Most Recent Most Helpful Highest Rating Lowest Rating Oldest

  • 5 star rating
    civic si
    By  ADRIAN,  a  Verified Buyer  on  July 26, 2026

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    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

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    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

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    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

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    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

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    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

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    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)
  • 5 star rating
    Great
    By  CHRIS,  a  Verified Buyer  from  Plymouth   on  July 24, 2026

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    Great product would recommend it to everyone
    Bottom Line

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

    YES (0) NO (0)
  • 5 star rating
    So far the oil is doing what oil should,
    By  GALE,  a  Verified Buyer  from  Grand Junction, Colorado   on  July 24, 2026

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    I have a high flow oil pump installed in my motor, oil pressure runs mid 50 psi and consumption hasn't been a problem yet. I believe amsoil is the result of the steabyness i was looking for.
    Bottom Line

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

    YES (0) NO (0)
  • 5 star rating
    Oil and wix xp filter
    By  ANTHONY,  a  Verified Buyer  from  Rockford Illinois   on  July 23, 2026

    Open report issue form

    Describe the issue

    Failed to verify captcha

    Cancel Submit
    Love the oil not so much the filter.I really wish you guys would get the amsoil ea17 filter back in stock, its been far to long they've been on back order.
    Bottom Line

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

    YES (0) NO (0)