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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 |
|---|---|---|
| ALMQT-EA | Quart | Each |
| ALMQT-CA | Case of 12 Quarts | Case of 12 |
| ALM1G-EA | Gallon Jug | Gallon Jug |
| ALM55-EA | 55 Gallon Drum | 55 Gallon Drum |
AMSOIL Signature Series 5W-20 100% Synthetic Motor Oil is a fully synthetic gasoline engine oil for late-model passenger cars, light trucks, SUVs, and turbocharged direct-injection engines that specify an SAE 5W-20 grade. The formulation meets API SP (Resource Conserving), API SN Plus, GM dexos1 Gen 3, ILSAC GF-6A, ACEA A1/B1, Chrysler MS-6395, and Ford WSS-M2C945-B1, and supports extended drain coverage up to 25,000 miles in normal service.
Signature Series 5W-20 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. The formula 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.
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 engines. Signature Series 5W-20 is built with an advanced detergent system designed to defend against the event. The formula delivers 100 percent protection against LSPI, with zero 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.
Turbochargers create extreme heat at the bearing, which can break weaker oils down and form deposits in a process known as turbo coking. The GM Turbo Coking Test is 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. Signature Series 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 in the GM turbo coking test.
Acid neutralization and detergency keep oil passages clean and slow the formation of varnish and sludge across long drain intervals. Signature Series 5W-20 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 formula 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.
Cold cranking viscosity governs how quickly oil reaches bearings and cam surfaces during a winter start. Signature Series 5W-20 delivers strong cold cranking viscosity in industry-standard ASTM D5293 Cold Crank Simulator testing required by SAE J300, and posts a CCS value of 4,385 cP at -30 C in the typical properties table. Once at operating temperature, the oil resists viscosity increase in the Sequence IIIH Engine Test (ASTM D8111) required by ILSAC GF-6 and API SP, holding viscosity gain under the standard threshold even at doubled test length and delivering 40 percent cleaner pistons than the standard requires.
Signature Series 5W-20 fits applications that require API SP (Resource Conserving), API SN Plus, or API SN. It also meets GM dexos1 Gen 3 (supersedes dexos1 Gen 2 and 6094M), ACEA A1/B1, Ford WSS-M2C945-B1, WSS-M2C945-A, WSS-M2C930-A, WSS-M2C960-A1, Chrysler MS-6395, and ILSAC GF-6A, GF-5, and GF-4. The grade is intended for engines that specifically call for an SAE 5W-20 viscosity 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, and oil level should be checked regularly. Signature Series 5W-20 is compatible with other conventional and synthetic motor oils, but mixing shortens oil life, reduces performance benefits, and is not supported for extended drain intervals. Aftermarket oil additives are not recommended for use 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) | 50.6 |
| Viscosity Index (ASTM D2270) | 153 |
| CCS Viscosity, cP at -30 C (ASTM D5293) | 4385 |
| Flash Point, C (F) (ASTM D92) | 220 (428) |
| Fire Point, C (F) (ASTM D92) | 244 (471) |
| Pour Point, C (F) (ASTM D97) | -50 (-58) |
| NOACK Volatility, percent weight loss (ASTM D5800) | 5.8 |
| High-Temperature High-Shear Viscosity at 150 C, cP (ASTM D5481) | 2.67 |
| Total Base Number (ASTM D2896) | 12.5 |
Signature Series 5W-20 is available as a quart bottle (product code ALMQT-EA), a case of 12 quarts (ALMQT-CA), a gallon jug (ALM1G-EA), and a 55 gallon drum (ALM55-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 product with the AMSOIL Vehicle Lookup Guide, compare grades and product positioning in the Signature Series Oil Guide, then order AMSOIL Signature Series 5W-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.
5W-20 is an SAE J300 viscosity grade. The 5W rating describes cold-start flow at low temperatures, and the 20 indicates a high-temperature operating viscosity well suited to many late-model passenger cars and light trucks built around tighter clearances and reduced internal friction for fuel economy. Signature Series 5W-20 is a 100 percent synthetic gasoline engine oil that meets API SP, ILSAC GF-6A, GM dexos1 Gen 3, and ACEA A1/B1.
Yes. AMSOIL Signature Series 5W-20 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.
The 5W-20 grade meets API SP (Resource Conserving), API SN Plus, and API SN. It also meets GM dexos1 Gen 3 (supersedes dexos1 Gen 2 and 6094M), ACEA A1/B1, Ford WSS-M2C945-B1, WSS-M2C945-A, WSS-M2C930-A, and WSS-M2C960-A1, Chrysler MS-6395, and ILSAC GF-6A, GF-5, and GF-4. The owner manual should list one of these service categories or OEM specifications before the oil is used.
Signature Series 5W-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 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.
Substituting a 5W-30 in an engine that specifies 5W-20 is not recommended. Signature Series 5W-20 is built for applications that require an SAE 5W-20 viscosity. Use the AMSOIL Vehicle Lookup Guide to confirm the correct viscosity for the vehicle.
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, limiting the heat-soak temperature increase to 3.6 percent against a 13 percent allowance, based on independent testing of Signature Series 5W-30 in the GM turbo coking test.
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.