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This AMSOIL 5W20 motor oil is a revolutionary product in the world of automotive lubricants. This 5W20 full synthetic engine oil is designed to offer exceptional wear protection, ensuring that your engine stays robust and resilient even under intense operating conditions. This oil is engineered to maintain its oil viscosity, offering a clean and efficient engine performance throughout its life. Unlike conventional oils, Signature Series doesn't lose its composure even at high temperatures. It reduces friction and prevents wear, making it an ideal choice for those in search of a 5W20 oil that can offer long-lasting reliability and superior performance, thereby protecting key components like the crankshaft, pistons and valves. It is spoken of well by many engine builders and fleet mechanics, as well as your standard car repair mechanics. The AMSOIL 5W20 Signature Series is sought after.

Further, this SAE 5W20 formulation ensures optimal fuel economy, aiding your vehicle in delivering the best performance without compromising efficiency. This makes it a preferred choice for daily drivers who demand the best from their commuter and city car driving vehicles. It is also very popular among Ford F150 owners! What sets this 5W20 synthetic oil apart from its peers is the extended drain interval. The Signature Series line offers unparalleled protection for an extended period, significantly reducing maintenance time and costs. The formulation is designed to keep engines clean and free of sludge, maintain oil viscosity and thickness, which in turn improves engine life. Even when compared with synthetic oils like Pennzoil Ultra Platinum 5W20 or Mobil 1 5W20, this oil has shown outstanding resistance to volatility, further asserting its capacity to protect your engine in high-stress situations.

In a nutshell, this AMSOIL 5W20 synthetic motor oil is a high-performance, full synthetic that not only protects and prolongs the life of your engine but also significantly improves its performance. Whether you're seeking reliability, fuel economy, or reduced maintenance, this product ticks all the boxes. Order this oil and either DIY or take it to a one stop quick lube and have it installed! Become an AMSOIL Preferred Customer and get up to 25% off on your order!


Key points to look at are:

  • Enhances engine protection by 75% against horsepower loss and wear(1).

  • Offers 50% greater cleaning power compared to AMSOIL OE Motor Oil.

  • Provides turbocharger protection that exceeds GM dexos1 Gen 2 specification requirements by 72%(2).

  • Exhibits 28% more acid-neutralizing capability than Mobil 1.(3)

  • Trusted by professional engine builders for reliability.

  • Ensures guaranteed protection for up to 25,000 miles or 1 year.

    • (Note 1) Engine protection data is derived from independent testing of AMSOIL Signature Series 0W-20, following ASTM D6891 as required by the API SN specification.

    • (Note 2) Turbocharger protection is based on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.

    • (Note 3) Acid-neutralizing power comparison conducted with Mobil 1 Annual Protection Full Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896, using oils purchased in July 2020.



AMSOIL Signature Series 5W20 Synthetic engine oil stands as a champion in the industry, promising the apex of performance, reliability, and longevity for your vehicle. This revolutionary synthetic motor oil lube, infused with advanced engineering, is designed to meet the most stringent conditions and demanding environments, including driving in Dallas Fort Worth traffic! It is tailored to serve the diverse needs of various vehicle engines and deliver impressive results consistently.

This engine oil works on a unique formulation. It utilizes synthetic base oils and fortified with an advanced additive package. This multi-faceted technology is the perfect blend to meet the expectations of modern high-performance engines, which need more from motor oil than merely lubricating the moving parts. AMSOIL 5W20 Signature Series caters to their myriad needs while enhancing their overall performance and ensuring that they stay protected in different conditions.

This synthetic oil delivers exceptional anti-wear protection, extending the lifespan of the engine. The robust synthetic formulation creates a strong film of protection around the engine components, such as cylinders, head gaskets, pistons and the camshaft, significantly reducing metal-to-metal contact during start-up and operation. This reduction of friction not only extends the life of the engine but also enhances its efficiency.

AMSOIL 0w20 Sequence Test

Extended drain cycles are another significant advantage of this 5W20 synthetic oil. It is designed to outlast conventional oils, providing protection that extends beyond the traditional oil change interval. Its durable synthetic formula and proprietary additives provide long-lasting protection that helps extend engine life and prevent the check engine light on!

One of the most prevalent issues that plague today's downsized, turbocharged engines is low-speed pre-ignition (LSPI). This 5W20 motor oil offers a robust solution to this problem, effectively protecting pistons from LSPI. It reduces the chance of these pre-ignition events that can cause severe engine and cylinder block damage.

Positive LSPI Prevention Test Result

LSPI damage of a piston where this product was not used.

Another area where this 100% synthetic oil shines is its role in turbocharger protection. Turbochargers operate in harsh, high-temperature conditions and are highly susceptible to deposits and wear. The oil provides a superior shield to turbochargers. Its resilient formulation resists heat and prevents deposits, ensuring the turbocharger performs optimally and lasts longer.

Clean GM Turbo

Coking test where a turbocharger was protected!

This product helps in preserving horsepower. The engine remains clean, thanks to the oil's exceptional detergency, which helps to keep the engine close to its factory-clean condition. This clean condition aids in maintaining maximum power and fuel efficiency throughout the oil's extended service life.

Clean Piston Test Result

Virtually clean piston after double the industry standard testing time period.

This synthetic motor oil is also designed to limit oil consumption. Its robust formulation helps to maintain the oil's viscosity, ensuring the oil does not volatilize and burn off in high-temperature operations. This characteristic not only reduces oil consumption but also emission of volatile organic compounds.

AMSOIL Low Number Sequence Test

Lastly, the cold-start performance of this 5W20 oil is unparalleled. The excellent low-temperature properties ensure rapid oil flow in cold starts, providing instant lubrication to vital components, such as the crankshaft and pistons, amongst other parts, reducing wear and prolonging engine life. This oil can be installed at any fast oil change location at any time of year.

AMSOIL Cold Crank Test

In a nutshell, this product offers these five key benefits:

  • Protection against wear: It significantly reduces metal-to-metal contact, providing an exceptional anti-wear shield.

  • Extended drain cycles: It provides long-lasting protection, surpassing the traditional oil change interval.

  • Protection against LSPI: It effectively safeguards pistons from the damages of low-speed pre-ignition.

  • Turbocharger protection: Its heat and deposit-resistant formulation ensure optimal performance and longevity of turbochargers.

  • Preserves horsepower and maintains viscosity: It keeps the engine clean, ensuring maximum power and fuel efficiency while reducing oil consumption.

AMSOIL Wear Test

Bearings after 100,000 mile test and almost look like new!

In conclusion, AMSOIL 5W20 100% Synthetic Motor Oil, with its advanced technology and diverse benefits, is the quintessential engine oil for any vehicle owner who seeks uncompromised engine protection, durability, and performance. Order this product direct for your next DIY oil change or take it to your local oil change near me installer or quick oil change lube shop for added protection and performance from this synthetic oil. Use the AMSOIL Lookup to find other products for your vehicle as well! Order this product today and DIY or take it to an oil change near me facility, like a Take 5 oil change location, a Jiffy Lube near me lube shop, a Valvoline instant facility, another one stop quick lube installer or your own motor mechanic to have it done professionally. 

Clean Turbocharger Oil Pick Up Test

Oil pick up screen virtually clean after testing!


AMSOIL Compare Oil Chart


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