Devoted to Protection™

Devoted to Protection™


Keep the car you love safe with 75% more engine protection against horsepower loss and wear than required by a leading industry standard*, extending the life of vital components like pistons and cams.

* Based on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification

World-Class Wear Protection


See why car enthusiasts, engine builders and racers also depend on AMSOIL fully synthetic oils to provide world-class wear protection for their vehicles.

We rigorously test our products to ensure you receive the highest quality synthetic lubricants on the market. AMSOIL Signature Series Motor Oil was subjected to testing to measure its ability to prevent wear, deposits and more.

The Proof


Your bearings shoulder the burden whenever you tow, haul or stomp the gas. AMSOIL delivers powerful protection for bearings and other critical components. An independent lab compared Signature Series head-to-head against a leading competitor in a 100,000-mile test. Signature Series provided far superior wear protection and kept bearings looking like new.* Upgrade to AMSOIL performance and drive with confidence.

*Testing conducted in an independent lab using AMSOIL Signature Series 5W-30 Synthetic Motor Oil and a leading synthetic-blend 5W-30 motor oil in Ford F-150 trucks with 3.5L twin-turbo engines.

Extended Protection


AMSOIL synthetic oils are hand-crafted for those who live for peak performance and demand the best protection – so you can continue to enjoy your vehicles to the fullest.

AMSOIL Signature Series Synthetic Motor Oil:

  • Fights Wear: 75% more engine protection against horsepower loss and wear.*
  • Battles Sludge: AMSOIL Signature Series Synthetic Motor Oil has 50% more detergents* to help keep oil passages clean and promote oil circulation. It provides 90% better protection against sludge.*
  • Fights Viscosity Breakdown: AMSOIL fights viscosity breakdown better than the competition,* providing superior protection of pistons, cams and bearings. 

* Based on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN PLUS specification. 
* vs. AMSOIL OE Motor Oil.
* Based on independent testing of AMSOIL Signature Series 5W-30 in the ASTM D6593 engine test for oil screen plugging as required by the API SN specification.  
* Based on independent testing of AMSOIL Signature Series, Schaeffer’s Supreme 9000 Full Synthetic, Lucas Synthetic, Valvoline Conventional Daily Protection, Mobil 1 Annual Protection and Pennzoil 5W-30 in the Kurt Orbahn Test. Oils purchased on 5/3/18.