AMSOIL PREMIUM PROTECTION 10W-40 100% SYNTHETIC MOTOR OIL

AMSOIL Premium Protection 10W-40 Synthetic Motor Oil delivers heavy-duty wear protection and thermal stability for engines that need a high-zinc, high-viscosity oil built to handle serious mechanical stress.

Older engines, flat-tappet cam designs, and high-mileage powerplants face challenges that modern low-viscosity, low-ZDDP motor oils simply aren't designed to address. Cam lobes, lifters, and bearings in these engines operate under extreme contact pressures, and reduced zinc levels in current API SN/SP oils can leave critical surfaces vulnerable. Engines subjected to hot operating temperatures, heavy loads, trailer towing, or off-road abuse compound the problem by accelerating oil breakdown and deposit formation.

HIGH-ZINC FORMULA FOR FLAT-TAPPET AND HIGH-PRESSURE COMPONENTS
Premium Protection 10W-40 is loaded with zinc and phosphorus anti-wear additives at levels specifically intended for engines with flat-tappet cams and high-tension valve springs. This is the oil for classic muscle cars, hot rods, vintage trucks, and older diesel engines where cam lobe and lifter wear is the primary failure mode. It resists viscosity loss due to mechanical shear, maintaining its protective film on gears, bearings, and cam lobes throughout the drain interval.

RESISTS OXIDATION AND HIGH-TEMPERATURE BREAKDOWN
Conventional 10W-40 petroleum oils are notorious for thickening, forming sludge, and burning off under sustained heat. AMSOIL Premium Protection uses synthetic base oils that dramatically reduce volatilization and oxidation at high temperatures. The result is a cleaner-running engine with less deposit buildup, whether air-cooled or liquid-cooled. This matters in applications like air-cooled motorcycle engines, generators running continuous duty cycles, and trucks pulling loads through summer heat where oil temperatures spike well beyond normal operating range.

WET-CLUTCH COMPATIBLE FOR MOTORCYCLES AND POWERSPORTS
This oil contains no friction modifiers, which makes it a direct fit for motorcycles and other equipment with wet-clutch transmissions. Friction modifiers found in many automotive motor oils cause clutch glazing and slippage in these applications. Premium Protection prevents that, delivering smooth clutch engagement and reduced clutch wear. It meets JASO MA specifications for motorcycle use, making it a versatile choice for riders running V-twins, sport bikes, or cruisers that call for a 10W-40 motor oil.

DUAL-PURPOSE GASOLINE AND DIESEL COVERAGE
One oil for multiple applications. Premium Protection 10W-40 is formulated to neutralize acids and disperse soot in diesel engines while also meeting the demands of gasoline-powered equipment. It covers a wide range of specifications including API SL, CI-4+, ACEA A3/B3, ACEA E3/E5, Cummins 20071/20072/20076/20077, Mack EO-M+, Mercedes-Benz 228.1/228.3/229.1, MAN 271/3275, MTU Type 2, Caterpillar ECF-1, Detroit Diesel 93K214, and Volvo VDS-2. That breadth of coverage means a single product can serve your classic Chevy small block, your diesel-powered skid steer, your Harley-Davidson, and your generator.

SPECIFICATIONS AND COMPATIBILITY
AMSOIL Premium Protection 10W-40 meets or exceeds the following specifications: API SL, SJ, SH, SG, API CI-4+, CI-4, CH-4, CF, CF-2, ISO-L-EMA, JASO MA, ACEA A3/B3, E3, E5, Caterpillar ECF-1, Cummins 20071/20072/20076/20077, Mack EO-M+/EO-M, MAN 271/3275, MTU Type 2, MB 228.1/228.3/229.1, Detroit Diesel 93K214, and Volvo VDS-2/VDS. It is compatible with conventional and synthetic motor oils, though mixing will reduce performance benefits and oil life. Aftermarket oil additives are not recommended.

SERVICE LIFE
Diesel engine normal service: up to 25,000 miles or one year, whichever comes first. Diesel engine severe service: up to 15,000 miles or one year. Gasoline engine normal and severe service: up to 15,000 miles or one year. Motorcycles, small engines, stationary engines, heavy equipment, and other applications: extend drain intervals based on oil analysis or follow the manufacturer's recommended drain interval. For best results, use AMSOIL Ea Full-Flow Oil Filters and replace at each oil change. Other oil filters should be changed at standard OEM intervals.