AMSOIL SIGNATURE SERIES 5W-30 100% SYNTHETIC MOTOR OIL

AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil delivers the kind of wear protection, cleanliness, and extended drain capability that separates a premium synthetic from everything else on the shelf. Built for drivers who put real miles on their engines and expect the oil to hold up the entire time.

Modern gasoline engines are working harder than ever. Turbochargers, gasoline direct injection, and tighter tolerances all generate more heat, more stress, and more opportunities for deposit formation. Stop-and-go driving, short trips, and extended intervals between oil changes compound the problem. A conventional or even mid-tier synthetic oil can lose its protective properties well before the next drain, leaving critical components like cam lobes, pistons, and turbo bearings exposed. Signature Series 5W-30 is formulated specifically to handle these conditions without compromise.

75% MORE PROTECTION AGAINST WEAR AND HORSEPOWER LOSS
The Sequence IVA engine test simulates extended stop-and-go driving, cycling between idle and elevated RPM for 100 hours while measuring camshaft wear across 84 locations. The API SN specification sets a maximum allowable average cam wear of 90 microns. AMSOIL Signature Series recorded just 20.28 microns, providing 75% more protection than the standard requires. That durability was further validated in a 100,000-mile independent test using Ford F-150 trucks with 3.5L EcoBoost twin-turbo engines, where Signature Series 5W-30 kept bearings looking like new and maintained horsepower and torque from start to finish. A strong fluid film separates metal surfaces under load, and robust anti-wear additives pick up where the fluid film leaves off, reducing metal-to-metal contact in high-stress regions like cam lobes and piston rings.

PREVENTS TURBO COKING IN DIRECT-INJECTION ENGINES
Turbochargers operate at extreme temperatures. When oil breaks down under that heat, it forms carbon deposits on the turbo bearing and shaft surfaces, a process known as turbo coking. Over time, this restricts oil flow through the turbo and degrades performance or causes outright failure. The GM turbo coking test subjects oil to 2,000 extreme heat-soak cycles and requires the oil to limit the temperature change within the turbocharger to 13% or less. Signature Series 5W-30 limited that increase to just 3.6%, protecting the turbocharger 72% better than the GM dexos1 Gen 2 specification requires. For owners of turbocharged vehicles like the Ford F-150 3.5L EcoBoost, Chevy Silverado 2.7L turbo, or any GDI turbo engine, this level of thermal stability matters at every oil change interval.

28% MORE ACID-NEUTRALIZING POWER THAN MOBIL 1
Combustion byproducts generate acids that attack engine surfaces and degrade oil over time. The Total Base Number (TBN) measures an oil's ability to neutralize those acids. AMSOIL Signature Series 5W-30 carries a TBN of 12.5 (ASTM D2896), delivering 28% more acid-neutralizing power than Mobil 1 Annual Protection Full Synthetic 5W-30 in independent testing. That reserve alkalinity keeps the oil working effectively for far longer, which is especially important during extended drain intervals or in engines that see heavy short-trip driving where moisture and fuel dilution accelerate acid buildup.

90% BETTER SLUDGE PROTECTION AND 50% MORE DETERGENTS
Sludge buildup starves engines of oil by plugging the oil pick-up tube screen. The Sequence VG engine test subjects a Ford 4.6L engine to 216 hours of sludge-inducing conditions. The industry standard allows 10% screen blockage before failure. Signature Series produced a screen virtually free of sludge, delivering 90% better protection than the standard requires in the ASTM D6593 engine test. The formulation carries 50% more detergent additives than AMSOIL OE Motor Oil, keeping oil passages clean and promoting consistent oil circulation throughout the engine. In the Sequence IIIH test (ASTM D8111), even after the test length was doubled to 180 hours at oil temperatures of 304°F, Signature Series delivered 40% cleaner pistons than the standard requires.

SUPERIOR COLD-CRANKING PERFORMANCE
Cold starts are when the most wear occurs. In ASTM D5293 cold-crank simulator testing at -30°C, Signature Series 5W-30 recorded a cranking viscosity of 3,968 cP. That is significantly lower than Royal Purple High Performance 5W-30 (4,500 cP), Lucas 5W-30 (5,000 cP), Driven LS30 5W-30 (5,750 cP), Red Line High Performance 5W-30 (6,100 cP), and Royal Purple HPS 5W-30 (6,100 cP). Lower cold-crank viscosity means faster oil flow to critical components at startup, reducing the dry-running window that causes the most engine wear.

100% LSPI PROTECTION
Low-speed pre-ignition is a destructive phenomenon in modern GDI and turbocharged engines where the fuel-air mixture ignites before spark-triggered ignition, potentially breaking piston ring lands and causing catastrophic damage. AMSOIL Signature Series 5W-30 achieved zero LSPI events across five consecutive tests in the engine test required by the GM dexos1 Gen 2 specification. That is complete protection in every test run.

SPECIFICATIONS AND COMPATIBILITY
AMSOIL Signature Series 5W-30 (ASL) meets or exceeds the following specifications: API SP (Resource Conserving), SN PLUS, SN; GM dexos1 Gen 3 (supersedes dexos1 Gen 2, LL-A-025, 6094M, and 4718M); ACEA A5/B5, A1/B1; Honda HTO-06; Ford WSS-M2C946-B1, WSS-M2C946-A, WSS-M2C929-A, WSS-M2C961-A1; Chrysler MS-6395; ILSAC GF-6A, GF-5, GF-4. This covers a wide range of vehicles including GM trucks and SUVs requiring dexos1, Ford F-150 and Explorer models specifying 5W-30, Honda Accord, CR-V, and Odyssey requiring HTO-06, and Chrysler/Dodge/Jeep vehicles calling for MS-6395.

Signature Series is compatible with other conventional and synthetic motor oils, though mixing will reduce performance benefits and shorten the oil's effective service life. Aftermarket oil additives are not recommended.

SERVICE LIFE
Normal service: Up to 25,000 miles, 700 hours of operation, or one year, whichever comes first. Severe service (commercial or fleet vehicles, excessive idling, frequent towing, hauling, plowing, or dusty conditions): Up to 15,000 miles, 700 hours of operation, or one year, whichever comes first. Modified engines (non-stock), racing vehicles, and vehicles using alternative fuels (E85, CNG, propane) are excluded from extended drain interval recommendations. When using non-AMSOIL oil filters, do not exceed 12,000 miles or one year unless longer intervals are recommended by the vehicle manufacturer. Always change the filter when changing the oil.