Heat, load and time are relentless enemies of an engine. Whether you’re pushing a high-performance car to its limits, hammering desert miles or towing up a mountain pass, your engine is constantly under stress. Modern engines make more power than ever while operating under tighter tolerances and higher temperatures, placing greater demands on motor oil. For enthusiasts who expect maximum performance, reliability and protection from their vehicles, choosing the right lubricant isn’t just maintenance – it’s part of the performance equation.
AMSOIL understands the demands of enthusiasts, and we have built our reputation around doing things differently. As an independently owned company, we have the freedom to pursue performance above profit. In fact, we didn’t just enter the market decades ago; we rewrote expectations of what motor oil can do.
The Pursuit of Performance
As a pilot and lieutenant colonel in the Minnesota Air National Guard, AMSOIL founder Al Amatuzio witnessed firsthand the extraordinary demands placed on aviation engines and the remarkable capabilities of synthetic lubricants used by the military that kept them running. His experience piloting cutting-edge jet aircraft showed Amatuzio how synthetic oil delivered protection conventional lubricants simply could not match, especially under extreme heat and stress.
That experience sparked a question that would change the course of the automotive lubricant industry: if synthetic oil is essential for high-performance aircraft, wouldn’t it provide benefits in automobiles? In the 1960s, motor oils were prone to breaking down under heat and thickening in cold weather, creating challenges for everyday drivers and those pursuing high-performance and off-road adventures. While most of the industry accepted those limitations, Amatuzio set out to find a better way.
After an intense period of research and development, Amatuzio developed the world’s first synthetic motor oil for automotive applications and by 1968 he was selling synthetic oil under the AMSOIL brand name. In the beginning, Amatuzio did everything himself in a tiny garage – from blending to packaging to distribution. He was determined to bring a product to market that provided consumers with benefits no one else was giving them. He wanted people to have the best. No compromises. It was a humble beginning for a revolutionary idea.
By 1972, AMSOIL cemented its place in automotive history when AMSOIL Synthetic Motor Oil became the world’s first synthetic motor oil to pass API testing requirements. Born from aerospace-inspired innovation and a refusal to accept conventional limits, that breakthrough proved synthetic oil could deliver superior protection, performance and longevity — and it forced an entire industry to follow a small company’s lead.
More than five decades later, that same pursuit of performance continues to drive the AMSOIL business model, and we continue to make premium synthetic lubricants for enthusiasts that demand the best. Now we are building on that legacy with the release of our newest motor oil formulation.
AMSOIL Signature Series 100% Synthetic Motor Oil is already regarded by many as the gold standard for engine protection and performance. But we made it even better. Our new formulation raises the bar for motor-oil performance, ensuring we are prepared to meet the future of increasingly demanding engines. But bold claims demand evidence, and testing performed at a third-party lab provides it.
Supporting Extended Drains
Extended-drain protection has always been a defining feature of Signature Series, and the next-generation formulation reinforces that legacy.
To demonstrate its performance while practicing extended drain intervals, we installed Signature Series 5W-30 Synthetic Motor Oil (ASL) in a 2025 Ford* F-150 Raptor* with a high-output 3.5L engine and strapped it into a dyno at a third-party lab for 125,000 miles (201,168 km). Oil was changed at 25,000-mile (40,234-km) intervals. Throughout the test, no oil consumption was observed, the additive package held strong, viscosity remained in grade and very low wear metals were produced.
Preserving Horsepower and Torque
When engines wear, power fades. AMSOIL Signature Series Synthetic Motor Oil helps engines run stronger, longer. To demonstrate, power sweeps were conducted on the dyno at the beginning of the 125,000-mile Raptor test and at the end. The conclusion was clear: AMSOIL Signature Series preserves horsepower and torque.1
As the graph shows, Signature Series maintained performance throughout the 125,000-mile test, even under the elevated stresses of a high-output engine.2
4X LSPI Protection
Low-speed pre-ignition (LSPI) is an abnormal combustion event that can occur in modern turbocharged gasoline direct-injection (GDI) engines, especially at low engine speeds and under high loads. LSPI happens when the air‑fuel mixture ignites earlier than the sparkplug fires due to small droplets of engine oil, often mixed with fuel, that can enter the cylinder and ignite under high heat and pressure. The industry has learned a lot about LSPI and how to formulate engine oil to help prevent the phenomenon; however, as oil ages over the course of its service life, that protection can fade.
The Sequence IX test is now used to evaluate a lubricant’s resistance to uncontrolled pre-ignition events under boosted, low-speed, high-load conditions. The standard Sequence IX test uses a Ford 2.0-liter EcoBoost engine, and it evaluates laboratory-aged oil. The oil is aged for 72 hours to simulate oil degradation over about 4,000 miles. AMSOIL modified the test to increase its severity and try to challenge Signature Series. All standard test protocols were followed, except the oil was aged for 25,000 miles in a high-output 3.5-liter EcoBoost in a Ford Raptor.
AMSOIL Signature Series far exceeded benchmarks. Even after 25,000 miles of use, AMSOIL Signature Series delivered four times more piston protection against LSPI,3 confirming that it is engineered to provide sustained LSPI protection, even while practicing extended drain intervals.
