AMSOIL EXTENDED-LIFE 10W-40 100% SYNTHETIC MOTOR OIL

AMSOIL Extended-Life 10W-40 100% Synthetic Motor Oil delivers 20,000-mile drain intervals and 37% more cleaning power than AMSOIL OE Synthetic Motor Oil, making it a smart upgrade for drivers who want extended protection without compromising engine cleanliness.

Modern gasoline engines, particularly turbocharged direct-injection (GDI) designs, put tremendous stress on motor oil. High combustion temperatures break down conventional and lower-tier synthetic oils, leading to viscosity changes, sludge formation, and increased oil consumption. Engines that see a mix of highway cruising and stop-and-go traffic need oil that holds up across a wide range of operating conditions, not just for the first few thousand miles.

RESISTS OIL BREAKDOWN OVER EXTENDED DRAIN INTERVALS
Oil that thickens or thins significantly during use creates problems. Thickened oil increases drag and fuel consumption. Thinned oil fails to maintain proper film strength on bearings and cylinder walls. AMSOIL Extended-Life 10W-40 maintains its viscosity under extreme conditions thanks to advanced synthetic base oils with a viscosity index of 158 (ASTM D2270). The NOACK volatility is just 5.2% weight loss (ASTM D5800), meaning very little of the oil's lighter fractions burn off at high temperatures. Lower volatility translates directly to reduced oil consumption and fewer top-offs between changes.

PROTECTS AGAINST LOW-SPEED PRE-IGNITION
LSPI is the spontaneous ignition of the fuel/air mixture before spark-triggered combustion. It occurs most often in turbocharged GDI engines operating at low RPM under high load, and a single LSPI event can crack a piston or bend a connecting rod. The chemistry behind LSPI is linked in part to oil formulation, specifically calcium-based detergent interactions with fuel droplets in the combustion chamber. AMSOIL Extended-Life 10W-40 uses a formulation specifically designed to guard against LSPI, providing protection in the turbocharged engines found in vehicles like the Jeep Grand Cherokee 2.0L turbo, Ford EcoBoost trucks, and GM 2.7L turbo-four equipped Silverados.

KEEPS ENGINES CLEAN WITH A BOOSTED ADDITIVE PACKAGE
Carbon deposits on intake valves, piston crowns, and ring lands rob engines of efficiency and power. Over time, sludge restricts oil passages and starves critical components of lubrication. AMSOIL Extended-Life 10W-40 is fortified with detergent and dispersant additives that neutralize acids, suspend contaminants, and resist sludge and carbon deposit formation. The result is 37% more cleaning power compared to AMSOIL OE Synthetic Motor Oil. For vehicles like the Nissan Xterra, Jeep Wrangler, or Ford F-150 with higher-mileage engines, that cleaning capability helps maintain performance and keep oil passages clear over the full drain interval. The total base number measures 10.7 (ASTM D2896), indicating strong acid-neutralizing reserve throughout the oil's service life.

BROAD COLD-WEATHER AND HIGH-TEMPERATURE PERFORMANCE
The 10W-40 viscosity grade gives this oil a wider operating range than a straight 40-weight. At cold temperatures, it flows readily at startup to reduce dry-start wear. The CCS viscosity at -25°C is 6,047 cP (ASTM D5293), and the pour point is -39°C / -38°F (ASTM D97). At the high end, the kinematic viscosity at 100°C is 15.4 cSt (ASTM D445), and the high-temperature/high-shear viscosity at 150°C is 4.6 cP (ASTM D5481). That high HTHS number provides strong film protection under heavy load and high operating temperatures. The flash point of 240°C (464°F) per ASTM D92 confirms excellent thermal stability.

REDUCES MAINTENANCE FOR PERSONAL AND FLEET VEHICLES
Extended drain intervals up to 20,000 miles or one year in normal service cut the number of oil changes significantly. For fleet managers running multiple vehicles, that means fewer shop visits, less downtime, and reduced waste oil disposal. For personal vehicle owners, it means changing oil on your schedule rather than being tied to a 5,000-mile reminder. The 10W-40 viscosity is a versatile choice for older naturally aspirated engines, trucks, and SUVs that call for a heavier weight oil.

Specifications and Compatibility
AMSOIL Extended-Life 10W-40 meets API SQ, SP, SN Plus and ACEA A3/B3, A3/B4 specifications. It is compatible with conventional and other synthetic motor oils, though mixing will shorten the oil's life expectancy and reduce its performance benefits. Aftermarket oil additives are not recommended for use with this product. AMSOIL does not support extended drain intervals where oils have been mixed.

Service Life
Normal Service: Up to 20,000 miles (32,000 km) or one year, whichever comes first, in personal vehicles not operating under severe service. Severe Service: Up to 12,000 miles (20,000 km) or one year, whichever comes first. Severe service conditions include commercial or fleet vehicles, excessive idling, frequent towing, hauling, plowing, or driving in dusty conditions. Modified (non-stock) engines, racing vehicles, and vehicles using alternative fuels (E85, CNG, propane, etc.) are excluded from extended drain interval recommendations. For best performance, use AMSOIL Oil Filters, which are designed for extended drain intervals. Do not exceed 12,000 miles (20,000 km) or one year with other brand filters unless longer intervals are recommended by the vehicle manufacturer. Always change the filter when changing oil. Check oil regularly to maintain proper fill levels.