AMSOIL has long used the ASTM D4172 Four-Ball wear Test and the DIN 51581 NOACK Volatility TEST as ways to demonstrate the superiority of AMSOIL motor oils over competing synthetic and petroleum motor oils. In fact, AMSOIL was the first to utilize the NOACK Volatility Test as a standard of performance excellence. Both the Four-Ball Wear Test and the NOACK Volatility Test, when put into graph form, provide a visual demonstration of where AMSOIL motor oils stand when out head to head with the competition.

However, AMSOIL motor oils have these additional benefits which are not so easily measured and put into graph form. AMSOIL spares no expense when it comes to additives, purchasing the best, most durable on the market. These additives keep AMSOIL motor oils shear stable, provide long-term performance against varnish and sludge, keep critical engine components clean and deposit-free and resist the harmful effects of rust, corrosion and foaming.

AMSOIL uses the best shear stable viscosity index improvers available. Critical to the extended drain capabilities of AMSOIL motor oil, top quality VI improvers ensure that the oil maintains its protective viscosity throughout extended drain intervals. AMSOIL motor oils surpass North American AAMA, Japanese JASO and European ACEA oil specifications for high temperature/high shear viscosity, withstanding shearing forces which cause conventional oils to thin out and lose viscosity. Oils with poor shear stability lose their viscosity relatively quickly, losing their ability to protect against metal-to-metal contact and wear, especially in high temperature conditions.

Combustion within the engine creates damaging, corrosive by-products. when fuel, soot and water mix, sludge and varnish deposits form on critical engine components. clogging oil passages, restricting oil flow and causing vital engine components to stick and malfunction. The motor oil's ability to neutralize acids and prevent the formation of sludge and varnish is critical to the life of an engine. Another feature of AMSOIL motor oils is its high TBN, which neutralizes acids and prevents corrosion, rust and other harmful effects of sludge and varnish. Rust inhibition is an especially important feature for engines subject to frequent short-trip operations and for stored engines.

Detergent/dispersants greatly reduce the formation of harmful sludge and varnish deposits. By keeping combustion by-products dispersed within the crankcase until they are removed by the oil filter, detergent/dispersants prevent them from combining to form larger, more harmful particles. AMSOIL uses top-of-the-line detergent/dispersant additives, keeping engines clean and deposit-free for extended drains.

In order to lubricate the rings and cylinder walls in an engine, motor oil is exposed to the heat and flame of burning gasoline. In the process, some of the oil also burns off. AMSOIL motor oils are engineered to burn as cleanly as possible, keeping combustion chamber walls clean and deposit- free and preventing ring sticking and breakage, pinging, engine knock and other problems that reduce an engine's efficiency.

During engine operation, air in the crankcase gets whipped into the motor oil, causing the oil to foam. The air bubbles within this foamed oil do not always collapse, inhibiting heat transfer and impeding lubrication. AMSOIL motor oils resist foaming, ensuring protection against the metal-to-metal contact and wear that occurs with foamy oils.

By using only the highest quality basestocks and additives, AMSOIL motor oils are capable of extended drain intervals, all while maintaining performance, providing long-term wear protection and fuel economy, keeping engines clean and deposit free, providing cold weather starts and protecting against rust and corrosion.