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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 Details
Engineered for enthusiasts seeking maximum protection and performance. Precision-formulated with cutting-edge technology and a longstanding devotion to making the world's best motor oil. The result: engine protection that blows the doors off the highest industry standards.

• 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
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. 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 unique synthetic formulation is inherently stable to resist oxidation and neutralize acids. Signature Series Motor Oil provides outstanding protection against deposits common to high-temperature engine environments. The tremendous heat and stress turbos create can cause some oils to break down and form harmful bearing deposits through a process known as turbo coking. Over time, turbos can suffer reduced performance or fail altogether.

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 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.

Preserves Horsepower
The extreme durability of Signature Series 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.
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
ASL1G (ASL1G-CA)
Gallon
Case of 4 Signature Series 5W-30 Synthetic Motor Oil
ASL30 (ASL30-EA)
30-Gallon Drum
Each
Signature Series 5W-30 Synthetic Motor Oil
ASL55 (ASL55-EA)
55-Gallon Drum
Each
Signature Series 5W-30 Synthetic Motor Oil
ASL27 (ASL27-EA) 275-Gallon Tote Each Signature Series 5W-30 Synthetic Motor Oil
Technical Information
Extra Information
What is the recommended drain interval for AMSOIL Signature Series Motor Oils?
Motor oil's service life can be greatly affected by vehicle operating conditions, so AMSOIL provides definitions for normal and severe service and recommends corresponding drain intervals for each. 
Normal Service – Up to 25,000 miles, 700 hours of operation or one year, whichever comes first, in personal vehicles not operating under severe service. 
Severe Service – Up to 15,000 miles, 700 hours of operation or one year, whichever comes first. Severe Service conditions include commercial or fleet vehicles; excessive idling; or frequent towing, hauling, plowing or driving in dusty conditions.

- Modified engines (non-stock), racing vehicles and vehicles using alternative fuels (E85, CNG, propane, etc.) are excluded from extended drain interval recommendations.
- Change at the vehicle manufacturer’s recommended drain interval outside U.S. and Canada.
- AMSOIL Ea® Full-Flow Oil Filters are designed for extended drain intervals. Do not exceed 12,000 miles or one year with other brand filters unless longer intervals are recommended by the vehicle manufacturer. Always change filter when changing oil. Check oil regularly to maintain proper fill levels
What are the differences between AMSOIL OE Synthetic Motor Oil, XL Synthetic Motor Oil and Signature Series Synthetic Motor Oil?
AMSOIL OE Synthetic Motor Oil is recommended for vehicle manufacturer-recommended oil change intervals; AMSOIL XL Synthetic Motor Oil is recommended for extended drain intervals of 12,000 miles or a year (whichever comes first) and AMSOIL Signature Series Synthetic Motor Oil is recommended for extended drain intervals of 25,000 miles or one year (whichever comes first). AMSOIL Signature Series Synthetic Motor Oil is formulated with advanced base oils and more robust additives, allowing longer extended drains than AMSOIL OE or XL Synthetic Motor Oils.   
What does the "W" represent in 5W-30 motor oil?
Answer: The "W" in 5W-30 motor oil stands for "winter" and indicates the oil meets or exceeds certain criteria for good low-temperature performance. Motor oil with SAE viscosity grade 5W-30 behaves like an SAE 30 oil at high temperatures and SAE 5W oil at low temperatures, providing the necessary fluidity for rapid starts and efficient engine operation at low temperatures. 
Testing proves AMSOIL Signature Series 5W-30 Synthetic Motor Oil provides more complete protection against damaging deposits than its competitors.
The push toward smaller, fuel-efficient yet powerful engines has driven the development of several key technologies. Gasoline direct injection (GDI) and turbochargers are now common features of passenger cars and light trucks. By 2020, industry experts predict that nearly every new vehicle will feature GDI technology, and the vast majority will be turbocharged. While these advanced technologies enhance performance, they also present serious challenges to motor oil.

The Turbocharger Trade-Off
Turbochargers push more air into the engine’s combustion chamber, providing better fuel-economy and performance but also creating intense engine temperatures. They often operate above 150,000 rpm on exhaust gases exceeding 1000°F. These extreme conditions cause some motor oils to break down and solidify into harmful deposits.

Vehicle manufacturers have long recommended different service intervals based on “normal” or “severe” driving conditions. Turbocharged vehicles are automatically included in the severe service category due to the extreme heat they generate. Motor oil with unique properties is required to combat the effects of intense temperatures.

Proof of Protection
AMSOIL Signature Series 5W-30 Synthetic Motor Oil was tested against two competing brands to determine its level of protection against deposit formation in high-heat applications.
TEOST33c Test Results
The TEOST 33C test (ASTM D6335) is an industry-standard bench test that simulates turbocharger operating conditions. According to the American Society for Testing and Materials (ASTM), it is “designed to predict the high temperature deposit forming tendencies of an engine oil.” To meet the API SN Resource Conserving and ILSAC GF-5 motor oil specifications that are often recommended by vehicle manufacturers, a 5W-30 motor oil must limit total deposit formation to 30 mg or less.

AMSOIL Signature Series 5W-30 Synthetic Motor Oil held the total weight of deposits to 7 mg, well under the 30 mg limit required by the API and ILSAC, while Royal Purple® API 5W-30 and Mobil1® Extended Performance 5W-30 came in just under the limit at 25.4 mg and 28.2 mg respectively. Signature Series 5W-30 Synthetic Motor Oil protects against harmful deposits on turbochargers 4X better than Mobil1® Extended Performance and 3.6X better than Royal Purple® in industry-standard testing*.

*Based on independent, third-party testing of AMSOIL® Signature Series 5W-30, Mobil1® Extended Performance 5W-30 and Royal Purple® API 5W-30 in the ASTM D6335 bench test required by the API SN Resource Conserving specification.
Test results represent the formulations available as of April 2016. Formulations were coded to eliminate bias during testing and samples were tested in random order. An appropriate number of trials of each oil were run to produce results at or above the 95 percent confidence level when compared to AMSOIL Signature Series 5W-30 Synthetic Motor Oil.
SIGNATURE SERIES OIL PROTECTS ENGINES FROM LOW-SPEED PRE-IGNITION 
Signature series oil protects engines from low-speed pre-ignition
OEMs have been aggressively downsizing engines to meet strict fuel economy and emissions standards while improving power and torque. Most new engines today use some combination of turbochargers, direct-fuel injection and variable valve timing to make more power than their larger counterparts while delivering improved fuel economy. This scenario seems like all upside for drivers. But today’s smaller, hotter-running engines pose significant challenges to lubricants. The latest is a phenomenon called low-speed pre-ignition (LSPI), also known as “super knock,” which can destroy pistons and connecting rods.

What Is LSPI?
LSPI is another version of engine knock, which has been around since engines were invented. In this case, it occurs under low-speed, high-torque conditions in turbocharged gasoline direct-injected engines – like when you’re taking off from a stoplight. LSPI is the spontaneous ignition of the fuel/air mixture prior to spark-triggered ignition. This form of pre-ignition is more destructive than typical engine knock.

No Magic Bullet
Just as your engine relies on a balanced network of components to function, the motor oil needed to protect it requires additives with the right qualities at the right quantities. While adding more of one ingredient or reducing another seems simple enough, small composition changes can have big impacts. We were determined to find a solution to the LSPI problem without sacrificing the performance of Signature Series in any way.

GM SPI Test
OEMs like GM have addressed the issue by designing tests to determine a motor oil’s ability to prevent LSPI. The GM SPI Test records the number of peak pressure events during high-load
operation in a turbocharged engine over a five-hour period. Passing the test is required to meet the GM dexos1® Gen 2 specification.

Test Parameters
Engine GM 2.0L EcoTec, LHU
Duration Five hours
Measures Number of peak pressure pre-ignition events
Simulates Turbocharged vehicle operating in high torque and at low speed
Requirement At least three of the five total tests with zero peak pressure LSPI
events and no tests with more than two peak pressure events

Perfect Score
We armed Signature Series with an advanced detergent system that protects against harmful deposits and LSPI. Signature Series Motor Oil achieved 100 percent protection against LSPI in the engine test required by the GM dexos1 Gen 2 specification – zero occurrences were recorded throughout five consecutive tests.
API SN PLUS Specification
API SN PLUS is a recently released specification that was requested by the automobile industry to protect passenger vehicles from LSPI. AMSOIL anticipated this change, and the current
formulations of Signature Series, XL and OE synthetic motor oil all meet or exceed the specification. Look for updated product labels featuring the new API “donut” in the near future. You can be confident that AMSOIL synthetic motor oils protect modern engines against LSPI, helping your vehicle deliver years of reliable service. 
1Based on zero LSPI events in five consecutive tests of AMSOIL Signature Series 5W-30 motor oil in the LSPI engine test required by the GM dexos1®  Gen 2 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.
AMSOIL 5W-30 Oil Testing
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