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AMSOIL Signature Series 5W-30 Synthetic Motor Oil

Signature Series 5W-30 Synthetic Motor Oil
Signature Series 5W-30 Synthetic Motor Oil
Product Highlight
Engineered for those who need the highest level of protection and performance possible. Featuring cutting-edge technology and a long-standing dedication to delivering the world's finest motor oil, this precision-formulated motor oil delivers on its promise.
As a consequence, engine protection that far exceeds even the most stringent industry requirements.

AMSOIL 5W30 synthetic oil is the next generation of motor oil. Unlike traditional oils, it contains more of the best quality base stocks and performance additives, giving it unsurpassed wear protection, viscosity control, anti-shear stability, and resistance to oxidation. It provides exceptional gas mileage and helps your engine run cleaner.

• 50% more cleaning power vs. AMSOIL OE Motor Oil
• Ideal for turbos & direct injection
• Guaranteed protection for up to 25,000 miles or 1 year

To buy AMSOIL 5W-30 at the cheapest price directly from AMSOIL Inc, simply add the Preferred Customer Membership to your cart.
Product Description
Protects Against Engine Wear
AMSOIL Signature Series Synthetic Motor Oil develops a strong fluid film that keeps metal surfaces separated while its robust anti-wear additives further reduce wear in metal-to-metal contact regions for maximum engine life.

AMSOIL 5W30 is a high-quality synthetic oil that increases fuel economy and reduces engine wear. It's been tested by top engine manufacturers and has been in use in their factories for decades. AMSOIL is a trusted brand with a lot of loyal fans.

The Sequence IVA Engine Test, which must be passed to meet the industry-standard API SN specification, simulates extended periods of stop-and-go driving. For 100 hours, the test engine cycles between 50 minutes of idling and 10 minutes of elevated rpm – conditions that encourage engine wear.

The camshaft is then measured for wear in 84 locations and an average score is determined. We used Signature Series 0W-20, the lightest viscosity in the line, to further increase the severity of the test. AMSOIL Signature Series Synthetic Motor Oil provided 75 percent more engine protection against horsepower loss and wear1 than required by the industry standard, extending the life of vital components like pistons and cams.
Cam lobes
Protects Pistons from Low-Speed Pre-Ignition
We armed Signature Series with an advanced detergent system that protects against harmful deposits and low-speed pre-ignition (LSPI). Most new engines feature gasoline direct injection (GDI), often combined with a turbocharger to boost power and improve fuel economy. These new technologies, when combined with a poorly formulated motor oil, promote LSPI and threaten engine operation. LSPI is the spontaneous ignition of the fuel/air mixture prior to spark-triggered ignition. It occurs in today's advanced engines and is much more destructive than typical pre-ignition. A properly formulated motor oil is critical for protecting your engine.

Original equipment manufacturers (OEMs) like GM* have addressed the issue by designing tests to determine a motor oil’s ability to prevent LSPI. Signature Series Synthetic Motor Oil achieved 100 percent protection against LSPI1 in the engine test required by the GM dexos1 Gen 2 specification - zero occurrences were recorded throughout five consecutive tests.

Protects Turbochargers
Our proprietary synthetic formulation is designed to withstand oxidation and neutralize acids.
The Signature Series Motor Oil protects against deposits that are common in high-temperature engine environments.
Turbo coking is a process in which some oils break down and form harmful bearing deposits as a result of the extreme heat and stress that turbos generate. Turbos can lose performance or even fail completely over time.

We challenged Signature Series to the GM Turbo Coking Test, which consists of 2000 cycles of extreme heat soaks. An oil must limit the temperature change within the turbocharger to 13 percent or less to pass the test. Signature Series limited the temperature increase to only 3.6 percent, protecting the turbocharger 72 percent better than required2 by the GM dexos1® Gen 2 specification.
Piston damage and shaft wear
Up To 25,000 Miles Protection
Extends Drains: Protection Guaranteed
AMSOIL 5W-30 Signature Series Synthetic Motor Oil provides reserve protection, allowing you to go longer between oil changes if you choose – up to 25,000 miles, 700 hours of operation or one year, whichever comes first*. Our unique synthetic formulation and long-drain additive system are inherently stable to resist oxidation and neutralize acids over longer periods. Signature Series is designed to deliver outstanding engine protection, cleanliness and performance over extended drain intervals – guaranteed. It provides peace of mind so you can fit oil changes into your schedule.

1 Based on independent testing of AMSOIL Signature Series 5w-30 motor oil, in the LSPI engine test as required for the GM dexos 1® Gen 2 specification.
2 Based on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
3 vs. AMSOIL OE Motor Oil
4 Based on independent testing of AMSOIL Signature Series 5W-30 in the ASTM D6593 engine test for oil screen plugging as required by the API SN specification.
* All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are developed by AMSOIL for use in the applications shown.

Oil plays a vital role in the performance of your car's engine. That's why it is important to use the right oil for your vehicle. AMSOIL 5W30 is designed to provide unbeatable protection and long-lasting performance, at an affordable price.

Preserves Horsepower
The extreme durability of Signature Series 5w30 Motor Oil ensures your engine runs stronger, for longer. We installed Signature Series 5W-30 Synthetic Motor Oil in a Ford* F-150 with a new 3.5L Ecoboost engine to test its ability to protect turbocharged direct-injection (TDGI) engines from torque and horsepower loss during extended drain intervals up to 25,000 miles. Power sweeps were done at the beginning and end of the test to evaluate horsepower and torque retention. As the graph shows, Signature Series helped maintain engine performance throughout the 100,000 mile test.
Preserves Horsepower
Limits Oil Consumption

Signature Series has a uniform molecular structure that limits evaporation and keeps it where it's needed most – protecting your engine. Volatility (burn-off) occurs when oil gets hot, causing lighter molecules to burn off or evaporate. This leads to oil thickening, additive imbalance, higher emissions and oil consumption. The NOACK Volatility test is the industry standard for evaluating motor oil high temperature evaporation. It measures the percentage of burn-off after a motor oil is placed under constant airflow at 482ºF for 1 hour. A lower number indicates a better resistance to evaporation. Signature Series falls far below the API limit for volatility, reducing the need for frequent oil top-offs and limiting vehicle emissions.
Limits Oil Consumption
Easier Cold-Starts

Signature Series Synthetic Motor Oil does not contain paraffins (wax) and stays fluid in temperatures of -58ºF and lower. Extreme cold causes other motor oils to thicken, starving vital moving parts of lubrication, accelerating wear and even preventing vehicles from starting. Signature Series provides 66 percent better cold-temperature performance for easier starting, better fuel economy, improved oil flow (as seen below) and reduced wear.
Easier Cold-Starts
Cold Pour Test
Maintains Protective Viscosity

We formulated Signature Series with superior thermal durability that resists breakdown better than conventional and synthetic motor oils. The Sequence IIIH Test uses the Chrysler 3.6L Pentastar engine to evaluate a motor oil's ability to resist the damaging effects of heat. The test is conducted with oil temperatures of 304ºF, 100ºF hotter than normal operation, to accelerate oil thickening and deposits. Despite the extreme conditions, Signature Series kept pistons clean and held thickening to only 6 percent, a minimal amount compared to the proposed specification limit of 150 percent.1 This stay-in-grade performance helps maintain maximum power and fuel economy while also ensuring advanced technologies like variable valve timing (VVT) operate as designed throughout the entire drain interval.
Maintains Protective Viscosity
Keeps pistons clean
1 Based on proposed ILSAC GF-5 Plus specification.
* All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are developed by AMSOIL for use in the applications shown.

5W-30 (ASL): API SN (Resource Conserving), SM...; GM dexosl Gen 2 (supersedes LL-A-025, 6094M and 4718M); ACEA A5/B5, A1/B1; Honda HTO-06; Ford WSS-M2C946-A, WSS-M2C929-A; Chrysler MS-6395; ILSAC GF-5, GF-4... Fortified with detergents that exceed the dexos 1 Gen 2 sulfated ash specification.

AMSOIL 5W30 synthetic motor oil is created from a high-performance synthetic base oil and a high-performance additive package designed to provide optimum wear protection. They're engineered for a wide variety of vehicle types and conditions. If you want to save 25% or more on AMSOIL 5W30 synthetic oil for your vehicle, then become a AMSOIL Preferred Customer!
Product Size
Code Package Size Unit of Measure Product
ASLQT (ASLQT-EA) Quart Each Signature Series 5W-30 Synthetic Motor Oil
ASLQT (ASLQT-CA) Quart Case of 12 Signature Series 5W-30 Synthetic Motor Oil
ASL1G (ASL1G-EA) Gallon Each Signature Series 5W-30 Synthetic Motor Oil
Case of 4 Signature Series 5W-30 Synthetic Motor Oil
ASL30 (ASL30-EA)
30-Gallon Drum
Signature Series 5W-30 Synthetic Motor Oil
ASL55 (ASL55-EA)
55-Gallon Drum
Signature Series 5W-30 Synthetic Motor Oil
ASL27 (ASL27-EA) 275-Gallon Tote Each Signature Series 5W-30 Synthetic Motor Oil
AMSOIL 5W-30 synthetic oil is a high-performance engine oil designed to provide a superior lubrication film on metal surfaces under high heat and load. The difference is AMSOIL was engineered for modern engines. This superior product has been proven to provide more protection for your engine then conventional oils.

AMSOIL synthetic motor oils are the world's best-selling synthetic oil (due to their quality and high performance)! They're designed, manufactured, and packaged in the USA. Their 5W-30 Motor Oil is the most popular oil for many car models because it's designed to deliver outstanding performance in today's tough driving environments. And because AMSOIL has been providing synthetic lubrication since 1972, they have a deep understanding of how engine oils work. AMSOIL synthetic oil can improve your vehicle's performance, reduce engine wear, prevent engine damage, and improve fuel economy.
Technical Information
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