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 |
|---|---|---|
| ATMQT-EA | Quart | Each |
| ATMQT-CA | Case of 12 Quarts | Case of 12 |
| ATM1G-EA | Gallon Jug | Each |
| ATM55-EA | 55 Gallon Drum | Each |
| ATM27-EA | 275 Gallon Tote | Each |
AMSOIL Signature Series 10W-30 100% Synthetic Motor Oil is a fully synthetic gasoline engine oil engineered for engines that specify an SAE 10W-30 grade, including many passenger cars, light trucks, SUVs, and V-8 powered vehicles. The formulation meets API SP (Resource Conserving), API SN Plus, and API SN along with ILSAC GF-6A, GF-5, and GF-4, and supports normal-service drain intervals up to 25,000 miles. It is built for owners and engine builders who want long oil life paired with strong wear, deposit, and turbocharger protection.
Signature Series develops a strong fluid film that keeps metal surfaces separated, reinforced by robust anti-wear additives that further reduce wear in metal-to-metal contact regions for maximum engine life. Signature Series provides 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 the ASTM D6891 Sequence IVA Engine Test required by the API SN specification. The result is added margin for vital components such as pistons and cams during long stop-and-go service.
Acid neutralization and detergency keep oil passages clean and slow the formation of varnish and sludge across 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. 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.
Turbochargers create extreme heat at the bearing, which 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. 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 testing of Signature Series 5W-30.
Low-speed pre-ignition (LSPI) is the spontaneous ignition of the fuel and air mixture before the spark fires, and it is most damaging in turbocharged gasoline direct-injection designs. Signature Series delivers 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.
Cold cranking viscosity governs how quickly oil reaches bearings and cam surfaces during a winter start. Signature Series delivers better cold cranking viscosity in industry-standard ASTM D5293 Cold Crank Simulator testing required by SAE J300. Once at operating temperature, Signature Series 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, and only 49.6 percent at twice the standard test length. The same doubled test produced 40 percent cleaner pistons than the standard requires.
An independent lab compared Signature Series 5W-30 against a leading synthetic-blend 5W-30 in Ford F-150 trucks with 3.5L twin-turbo engines across a 100,000-mile test. Signature Series delivered far superior wear protection and kept bearings looking like new.
Signature Series 10W-30 covers applications that require any of the following specifications: API SP (Resource Conserving), API SN Plus, API SN; ACEA A5/B5, A1/B1; Ford WSS-M2C205-A; Chrysler MS-6395; GM LL-A-025, 6094M, 4718M; and ILSAC GF-6A, GF-5, GF-4. The grade is intended for engines that specifically call for an SAE 10W-30 viscosity, common in passenger cars, half-ton and three-quarter-ton trucks, SUVs, and high-mileage vehicles in the United States and Canada market.
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. Signature Series 10W-30 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.
| Property | Value |
|---|---|
| Kinematic Viscosity at 100 C, cSt (ASTM D445) | 10.0 |
| Kinematic Viscosity at 40 C, cSt (ASTM D445) | 62.3 |
| Viscosity Index (ASTM D2270) | 147 |
| CCS Viscosity, cP at -25 C (ASTM D5293) | 4278 |
| Flash Point, C (F) (ASTM D92) | 230 (446) |
| Fire Point, C (F) (ASTM D92) | 256 (492) |
| Pour Point, C (F) (ASTM D97) | -47 (-52) |
| NOACK Volatility, percent weight loss (ASTM D5800) | 4.1 |
| High-Temperature High-Shear Viscosity at 150 C, cP (ASTM D5481) | 3.11 |
| Total Base Number (ASTM D2896) | 12.5 |
Signature Series 10W-30 is available in a quart bottle (product code ATMQT-EA), case of 12 quarts (ATMQT-CA), gallon jug (ATM1G-EA), 55-gallon drum (ATM55-EA), and 275-gallon tote (ATM27-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 for the vehicle with the AMSOIL vehicle lookup, review viscosity choices and product positioning in the gasoline motor oil products, then order AMSOIL Signature Series 10W-30 100% Synthetic Motor Oil.
I’ve been using AMSoil for so long I don’t remember when I started, but suffice to say I believe it’s the best oil on the market and when paired with the preferred customer membership it’s the the best value too.
Would recommend this to a friend.
The engine seems to run better
Would recommend this to a friend.
First time using this in my 2018 Silverado. So far it appears to be excellent. Quiet and smooth engine running. Will be using this oil exclusively from now on.
Would recommend this to a friend.
Yes. AMSOIL Signature Series 10W-30 is a 100 percent synthetic gasoline engine oil. The formulation is paired with a long-drain additive system that is inherently stable against oxidation and acid buildup over extended drain periods.
Signature Series 10W-30 meets API SP (Resource Conserving), API SN Plus, and API SN, along with ILSAC GF-6A, GF-5, and GF-4. It also satisfies ACEA A5/B5 and A1/B1, Ford WSS-M2C205-A, Chrysler MS-6395, and GM LL-A-025, 6094M, and 4718M. The owner manual should list one of these service categories before the oil is used.
Signature Series 10W-30 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, including towing, hauling, plowing, excessive idling, fleet duty, or dusty operating environments, is limited to 15,000 miles (24,140 km), 700 hours, or one year. AMSOIL Oil Filters are recommended to take full advantage of the extended interval.
Both grades share the same SAE 10W cold-cranking rating, so cold-start flow is similar. The second number is the high-temperature operating viscosity, where SAE 30 is thinner than SAE 40 at full operating temperature. The owner manual viscosity is the right reference, and the AMSOIL vehicle lookup can confirm the correct grade for the application.
No. SAE 30 is a single-grade oil rated only at high temperature, while 10W-30 is a multi-grade oil that flows like an SAE 10W at low temperature and protects like an SAE 30 at operating temperature.
The detergent system targets 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 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.