AMSOIL Launches Next-Generation Signature Series Synthetic Motor Oil

AS SEEN IN OUR Tread Sept/Oct 2026 ISSUE – Buy Now!

The Next Generation of AMSOIL Signature Series 100% Synthetic Motor Oil is Out Now

If you spend enough time driving off-road, you learn fast: heat, load, and time are relentless. Whether you’re crawling over rocks, hammering desert miles, or towing deep into the backcountry, your engine is constantly being pushed to the edge—and what’s protecting it matters.

AMSOIL understands the demands of enthusiasts and has built its reputation around doing things differently. As an independently owned company, they have the freedom to pursue performance above profit. In fact, the company didn’t just enter the market decades ago; it 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 like the F-80 Shooting Star 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 the company continues to make premium synthetic lubricants for enthusiasts that demand the best. The company that was founded on exceeding expectations now builds on that legacy with the release of its 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 AMSOIL has made it even better. Their new formulation raises the bar for motor-oil performance, ensuring they 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, Signature Series 5W-30 Synthetic Motor Oil was poured into a 2025 Ford F-150 Raptor with a high-output 3.5L engine and then strapped to a dyno at a third-party lab for 125,000 miles. Oil was changed at 25,000-mile intervals. Throughout the test, no oil consumption was observed, the additive package held strong, viscosity remained in grade, and very few wear metals were produced.

Preserving Horsepower and Torque

When engines wear, power fades. AMSOIL Signature Series Synthetic Motor Oil helps engines run stronger and longer. To demonstrate that, 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[1.1] 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 spark plug 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 2.0L 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 to challenge the Signature Series. All standard test protocols were followed, except the oil was aged for 25,000 miles in a high-output 3.5L 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 [3.1]confirming that it is engineered to provide sustained LSPI protection, even while practicing extended drain intervals.

Reduced Volatility

Volatility directly affects oil consumption, deposit formation, and long-term protection. Signature Series was evaluated in this area using the NOACK volatility test.

The NOACK is the industry-standard method used to measure how much motor oil evaporates when exposed to high temperatures over a set period. First, a weighed sample of motor oil is placed in a test apparatus and heated to 250°C (482°F), and airflow is introduced to simulate real-world evaporation conditions. The sample is held at this temperature and airflow continuously for 60 minutes. The oil is weighed again, and the mass loss is calculated.

The percentage change is the NOACK volatility result—a direct indicator of how well an oil resists evaporation in extreme environments. A lower percentage indicates better resistance to evaporation and, therefore, better ability to maintain its viscosity and protective film under extreme heat.

The NOACK Volatility Test allows a maximum of 15% mass loss to meet the ILSAC GF-7 specification. AMSOIL Signature Series had a result of 7.2%, delivering two times better protection against volatility,1[4.1] helping reduce oil consumption, minimizing top-offs, and keeping engines cleaner over time. Lower volatility translates into tangible benefits for drivers: less evaporation, fewer top-offs, more protection.

Industry-Leading Piston Cleanliness

Keeping pistons clean is essential for maintaining efficiency, power, and reliability—and it’s an area where Signature Series excels. The Sequence IIIH test was deployed to measure its ability to protect pistons from deposit formation.

The Sequence IIIH test is an industry-standard test designed to evaluate motor oil in several key performance areas. It’s a 90-hour test that essentially simulates driving a fully loaded pickup towing a heavy trailer up a long mountain grade in the desert for 3,000 miles without a break, and it must be passed to meet API and ILSAC specifications.

The new Signature Series formulation delivered outstanding results in the test, providing 72% more protection against piston deposit formation than industry standards.

Results in the Sequence IIIH test are a good indicator of how well an oil will perform in the real world. It is common for motor oils to barely pass the standard test with minimum passing scores. Signature Series, on the other hand, is barely challenged by Sequence IIIH.

After the test, the engine is torn down and the pistons are examined. They receive a score based on weighted piston deposits. The higher the score, the cleaner the oil kept the pistons. After the standard 90-hour Sequence IIIH test, the new Signature Series formulation received the highest rating ever achieved at the lab that performed the test—and that lab performs testing for many different oils.

So, to further challenge the formulation, AMSOIL asked the third-party lab to double the length of the industry-standard test, and Signature Series continued to outperform expectations. Even after doubling the Sequence IIIH test, Signature Series delivered cleaner pistons than required by the industry standard—providing 31% better protection than required.

No Sludge, Just Protection

Sludge formation can starve engines of oil, restrict critical oil passages, impair heat transfer, and accelerate wear on vital components, often leading to overheating, reduced efficiency, and catastrophic engine damage.

To demonstrate real-world sludge prevention, Signature Series was subjected to a demanding test. In the 125,000-mile accumulation study on a Ford Raptor, Signature Series demonstrated 0% oil-screen plugging. The conclusion is straightforward: AMSOIL Signature Series prevents sludge.

Always Driving Forward

Out on the trail, you don’t get second chances, so you run what you trust. From high-load climbs to long hauls in punishing heat and cold, today’s engines are pushed harder than ever, and the oil behind them must keep up. The next-generation AMSOIL Signature Series has been formulated to provide reliability and confidence to explore further.

The new formula doubles down on what matters most: tighter viscosity control when things get hot, stronger resistance to deposits and sludge, cleaner engine components, lower volatility, and reliable protection when temps drop. In short, it’s built to handle abuse and keep delivering.

Modern engines are evolving fast, and that means tighter tolerances, more heat, and new challenges for lubrication. That’s why the latest Signature Series formula isn’t just an update—it’s the product of relentless testing and the freedom to engineer for performance without compromise.