AMSOIL synthetic motor oil uses naturally shear-resistant base oils combined with top-tier, shear-stable viscosity improvers that withstand extreme heat and shearing forces. Not only does AMSOIL exceed industry standards and outperform competing brands, it fights viscosity breakdown 46% better than Mobil 1.

AMSOIL Inc. is an American corporation based in Superior, Wisconsin that primarily formulates and packages synthetic lubricants, fuel additives, and filters. Company founder Albert J. Amatuzio developed several synthetic motor oil formulations throughout the mid-to-late 1960s.

AMSOIL oils are formulated with a patented synthetic (synthesized or synthetically combined) base stock oil technology, which produces advantages far beyond other lubricants. And we like to think of it as art and science together.

the USA AMSOIL synthetic lubricants are made in the USA using global components. Developing innovative products and manufacturing to high quality standards have become our industry trademark and continue to drive worldwide demand.

AMSOIL synthetic car engine oil withstands extreme heat and shearing forces, exceeding industry standards and outperforming competing brands. In fact, it fights viscosity breakdown 46 percent* better than Mobil 1.

AMSOIL synthetic lubricants deliver wear protection, engine cleanliness and fuel efficiency conventional oils simply can't match.

AMSOIL motor oils are designed to deliver enhanced performance and extended drain intervals, justifying any higher price. AMSOIL offers premium products that rightfully command a premium price. Like anything of real value, however, the true consumer cost doesn't end with the purchase price.

founder Al Amatuzio For AMSOIL founder Al Amatuzio, that dream was to develop world-class synthetic lubricants. More than 40 years later, not only have Amatuzio's dreams been realized, but the company he founded continues to push the industry forward with innovative products that deliver tangible, real-world benefits.

At AMSOIL, we use “100% synthetic” on our product labels. We think it's the most straightforward and clear descriptor of the product you're buying, and it's aligned with industry definitions and practices. It's vital to remember a key point: motor oil is more than just base oils.

A rule of thumb for AMSOIL Signature Series Synthetic Motor Oil is guaranteed for 25,000 miles/12 months (15,000 miles/12 months in severe service). AMSOIL XL Synthetic Motor Oil is guaranteed for 10,000 miles/6 months, or longer where recommended by electronic oil life monitoring systems.

AMSOIL synthetic car engine oil withstands extreme heat and shearing forces, exceeding industry standards and outperforming competing brands. In fact, it fights viscosity breakdown 46 percent* better than Mobil 1.