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AMSOIL Gasoline Motor Oil
AMSOIL Signature Series is the top gasoline motor oil in the AMSOIL lineup, built for strong wear protection, clean operation, and dependable performance in demanding service.
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| Product code | Package size | Unit of measure |
|---|---|---|
| ASMQT-EA | Quart | Each |
| ASMQT-CA | Case of 12 Quarts | Case of 12 |
| ASM1G-EA | Gallon Jug | Gallon Jug |
| ASM55-EA | 55 Gallon Drum | 55 Gallon Drum |
AMSOIL Signature Series 0W-20 100% Synthetic Motor Oil is a fully synthetic gasoline engine oil engineered for late-model passenger cars, light trucks, and SUVs that specify an SAE 0W-20 grade. The formulation meets API SP (Resource Conserving), API SN PLUS, API SN, GM dexos1 Gen 3, ACEA A1/B1, and ILSAC GF-6A service categories and supports drain coverage of up to 25,000 miles in normal service. Signature Series 0W-20 is built for enthusiasts, daily drivers, and engine builders who want a strong margin for wear, deposits, and turbocharger heat in modern fuel-efficient engines.
The Sequence IVA Engine Test simulates 100 hours of stop-and-go driving, cycling between 50 minutes of idling and 10 minutes of elevated rpm, then measures camshaft wear in 84 locations. Signature Series 0W-20, the lightest viscosity in the gasoline line, was selected for the test to increase severity. The oil provided 75 percent more engine protection against horsepower loss and wear than required by the industry standard, based on independent testing of Signature Series 0W-20 in ASTM D6891 as required for the API SN PLUS specification. The result is added margin for pistons, cams, and other vital components during long stop-and-go service.
Low-speed pre-ignition (LSPI) is the spontaneous ignition of the fuel and air mixture before the spark fires, and it can fracture pistons and break ring lands in turbocharged gasoline direct-injection engines. Signature Series carries an advanced detergent system designed against the event. The oil delivered 100 percent protection against LSPI, with zero LSPI events recorded in five consecutive runs of Signature Series, XL, and OE 5W-30 in the LSPI engine test required for the GM dexos1 Gen 2 specification.
Turbocharger bearings see extreme heat that can break weaker oils down and form deposits in a process called turbo coking. Signature Series passed the GM Turbo Coking Test, a 2,000-cycle heat-soak protocol where an oil must keep the temperature change inside the turbocharger to 13 percent or less to pass. The formula limited the increase to 3.6 percent, protecting the turbocharger 72 percent better than required by the GM dexos1 Gen 2 specification, based on independent testing of Signature Series 5W-30.
Strong detergency and acid neutralization keep oil passages clean and slow varnish and sludge over long drain intervals. Signature Series carries 50 percent more detergents than AMSOIL OE Motor Oil and delivers 28 percent more acid-neutralizing power than Mobil 1, based on independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30 and Signature Series 5W-30 in ASTM D2896 with oils purchased July 2020. The formulation also provides 90 percent better protection against sludge in the ASTM D6593 oil screen plugging engine test required by the API SN specification, leaving the oil pick-up tube screen virtually free of sludge.
The 0W rating sets cold-start performance, and Signature Series 0W-20 posts a CCS Viscosity of 5,122 cP at -35 degrees Celsius in ASTM D5293 Cold Crank Simulator testing required by SAE J300. Once at operating temperature, the formula resists viscosity increase, posting only a 0.1 percent gain in the Sequence IIIH Engine Test (ASTM D8111) required by ILSAC GF-6 and API SP. At double the standard test length, the oil delivered 40 percent cleaner pistons than required by the standard, based on independent testing of Signature Series 5W-30.
Signature Series 0W-20 is built for engines that specifically call for an SAE 0W-20 viscosity grade. The grade meets API SP (Resource Conserving), API SN PLUS, and API SN; GM dexos1 Gen 3 (supersedes dexos1 Gen 2 and 6094M); ACEA A1/B1; Ford WSS-M2C947-B1, WSS-M2C947-A, and WSS-M2C962-A1; Chrysler MS-6395; and ILSAC GF-6A, GF-5, and GF-4.
AMSOIL Oil Filters are designed for extended drain intervals. With other-brand filters, the interval should not exceed 12,000 miles (19,312 km) or one year unless the vehicle manufacturer recommends a longer interval. The filter should always be changed when the oil is changed, and oil level should be checked regularly. Signature Series is compatible with other conventional and synthetic motor oils, but mixing shortens oil life and reduces performance benefits, and extended drain intervals are not supported when oils have been mixed. Aftermarket oil additives are not recommended with AMSOIL synthetic motor oils.
| Property | Value |
|---|---|
| Kinematic Viscosity at 100 C, cSt (ASTM D445) | 8.8 |
| Kinematic Viscosity at 40 C, cSt (ASTM D445) | 47.1 |
| Viscosity Index (ASTM D2270) | 169 |
| CCS Viscosity, cP at -35 C (ASTM D5293) | 5122 |
| Flash Point, C (F) (ASTM D92) | 220 (428) |
| Fire Point, C (F) (ASTM D92) | 244 (471) |
| Pour Point, C (F) (ASTM D97) | -53 (-63) |
| NOACK Volatility, percent weight loss (ASTM D5800) | 8.5 |
| High-Temperature High-Shear Viscosity at 150 C, cP (ASTM D5481) | 2.67 |
| Total Base Number (ASTM D2896) | 12.5 |
Signature Series 0W-20 is available in a quart bottle (product code ASMQT-EA), a case of 12 quarts (ASMQT-CA), a gallon jug (ASM1G-EA), and a 55 gallon drum (ASM55-EA). Using AMSOIL synthetic lubricants does not void a new vehicle or equipment manufacturer warranty, and all AMSOIL lubricants and filters are covered by the AMSOIL Limited Warranty. Match the right grade to the vehicle with the AMSOIL Vehicle Lookup Guide, compare 0W-20 product tiers in the 0W-20 Oil Guide, then order AMSOIL Signature Series 0W-20 100% Synthetic Motor Oil.
Did a recent oil change in my 2020 Cadillac XT6 and used this oil. The vehicle has alittle over 90k. The oil appears to have quieted down lifter noise and engine runs very smooth.
Would recommend this to a friend.
Its the best syhthetic oil out there
Would recommend this to a friend.
My son's 1991 Miata 1.6L with 190k miles has had a worsening lifter tick since we bought it almost a year ago. I use Amsoil in ALL of my vehicles so in this Miata we use the Mazda rec'd 10w30 Amsoil High Mileage. I trust this oil to protect the engine, even when it's making noise, and even while my son drives "spiritedly" pretty much at all times! We're not ready to build a fresh engine for this car just yet so I decided to try out Signature Series 5w-50 and see if the added viscosity would help quite the lifter tick. I am happy to say that since the first startup after the 5W-50 oil change, we have not heard the lifter tick even once in the last 1000 miles of driving. Yes, it's just a bandaid, but it'll do just fine until we get around to the engine rebuild and a new set of lifters.
Would recommend this to a friend.
0W-20 is an SAE J300 viscosity grade. The 0W rating describes cold-start flow, while the 20 indicates a high-temperature operating viscosity targeted at modern fuel-efficient engines. 0W-20 engines use tight tolerances and reduced friction to support fuel economy and emissions targets, so the viscosity grade listed in the owner manual should be followed.
Yes. Signature Series 0W-20 is a 100 percent synthetic gasoline engine oil paired with a long-drain additive system that resists oxidation and acid buildup over extended drain intervals.
Signature Series 0W-20 meets API SP (Resource Conserving), API SN PLUS, and API SN. The grade also covers GM dexos1 Gen 3 (supersedes dexos1 Gen 2 and 6094M), ACEA A1/B1, Ford WSS-M2C947-B1, WSS-M2C947-A, and WSS-M2C962-A1, Chrysler MS-6395, and ILSAC GF-6A, GF-5, and GF-4. The owner manual should list one of these service categories before the oil is used.
Signature Series 0W-20 supports drain intervals up to 25,000 miles (40,200 km), 700 hours of operation, or one year, whichever comes first, for normal service in personal vehicles inside the United States and Canada. Severe service is capped at 15,000 miles (24,140 km), 700 hours, or one year. AMSOIL Oil Filters are recommended to take full advantage of the extended interval.
Substituting a viscosity grade changes the oil film at operating temperature and is not recommended unless the vehicle manufacturer lists the alternate grade for that engine. Drivers running an engine that calls for 5W-20 or 5W-30 should confirm the recommended grades in the AMSOIL Vehicle Lookup Guide before changing viscosities.
The detergent system is designed against low-speed pre-ignition events common to turbocharged direct-injection designs, and Signature Series provides turbocharger protection 72 percent better than required by the GM dexos1 Gen 2 turbo coking test, based on independent testing of Signature Series 5W-30.
No. Using AMSOIL synthetic lubricants does not void a new vehicle or equipment manufacturer warranty, and all AMSOIL lubricants and filters are covered by the AMSOIL Limited Warranty.