Guaranteed Protection

Serious horsepower doesn’t just happen; you set the bar high across the board, from spark plugs to motor oil. At AMSOIL, we take protecting your ride as seriously as you do. Formulated to meet the demands of professional engine builders, our products deliver bulletproof protection. How good is it? With Signature Series, you can confidently go 25,000 miles (40,200 km) between changes. Signature Series was installed in a Ford* F-150 engine for a 100,000-mile (160,000-km) test by an independent third-party laboratory. During the test, the drain intervals were extended up to 25,000 miles (40,200 km). Horsepower and torque were measured at the start and end of the test. After 100,000 miles (160,000 km), the data shows Signature Series helped the engine maintain excellent horsepower and torque. The test engine was torn down and examined for signs of wear and sludge. The cylinder heads were clean, and the cams and bearings were virtually free from wear. Even after 100,000 miles (160,000 km) of extended drain intervals, the engine looked and performed like new.