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Signature Series 5W-30 Synthetic Motor Oil
Product code : ASLQT-EA
A New Level of Motor Oil Technology
• 75% more engine protection against horsepower loss and wear.1
• 50% more cleaning power vs. AMSOIL OE Motor Oil
• Protects turbochargers 72% better than required2 by the GM dexos1 Gen 2 specification.
• Trusted by professional engine builders
• Guaranteed protection for up to 25,000 miles or 1 year
1Based on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.
2Based on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
• 75% more engine protection against horsepower loss and wear.1
• 50% more cleaning power vs. AMSOIL OE Motor Oil
• Protects turbochargers 72% better than required2 by the GM dexos1 Gen 2 specification.
• Trusted by professional engine builders
• Guaranteed protection for up to 25,000 miles or 1 year
1Based on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.
2Based on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
Signature Series 5W-30 Synthetic Motor Oil
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.
See the Product Data Bulletin for full details.
Fights Engine Wear - 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.
- Develops a strong fluid film that keeps metal surfaces separated.
- Robust anti-wear additives further reduce wear in metal-to-metal contact regions for maximum engine life.
1Based on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.
Signature Series Fights Wear
75% more engine protection against horsepower loss and wear.A

ABased on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.
Signature Series Fights Viscosity Breakdown
AMSOIL fights viscosity breakdown better than the competition,O providing superior protection of pistons, cams and bearings.

OBased upon independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30, Schaeffer’s Supreme 9000 5W-30, Lucas Synthetic 5W-30, Valvoline Conventional Daily Protection 5W-30, Pennzoil 5W-30 and AMSOIL Signature Series 5W-30 in the Kurt Orbahn test. Oils purchased on 05/03/18.
Signature Series Delivers Powerful Protection
AMSOIL delivers powerful protection. How good is it? An independent lab compared AMSOIL synthetic motor oil head-to-head against a leading competitor in a 100,000-mile test.P AMSOIL provided far superior wear protection and kept bearings looking like new.

PTesting conducted in an independent lab using AMSOIL Signature Series 5W-30 Synthetic Motor Oil and a leading synthetic-blend 5W-30 motor oil in Ford F-150 trucks with 3.5L twin-turbo engines.
Signature Series Protects Against LSPI
AMSOIL Synthetic Motor Oils achieved 100% protection against LSPI.B

Example of piston damage due to an LSPI event observed during the testing of a competitor’s motor oil. The red arrows indicate sections of the ring land that have broken away from the piston.
BBased on zero LSPI events in five consecutive tests of AMSOIL Signature Series, XL and OE 5W-30 Motor Oil in the LSPI engine test required by the GM dexos1 Gen 2 specification.
Signature Series Resists Viscosity Increase
Signature Series is barely challenged by the industry-standard testing, demonstrating only a 0.1% viscosity increase. Even when the test length is doubled, AMSOIL delivered twice the viscosity control required by the standard.GG

GGBased on independent testing of AMSOIL Signature Series 5W-30 in the Sequence IIIH Engine Test (ASTM D8111), required by the ILSAC GF-6 and API SP specifications.
Keeps Engines Clean - Formulated with superior thermal durability that resists breakdown and keeps pistons clean.
- Controls heat and minimizes performance-robbing deposits.
- Maximizes engine life and performance.
Helps Keep Engines Cleaner
Signature Series is fortified with a heavy treatment of detergent additives, delivering 28 percent more acid-neutralizing power than Mobil 1* and helping engines stay cleaner, longer.LL
LLBased upon independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896. Oils purchased July 2020.
Signature Series Guards Turbos
Protects turbochargers 72% better than requiredC by the GM dexos1* Gen 2 specification.

CBased on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
Signature Series Cleans
Signature Series has 50% more detergentsD to help keep oil passages clean and promote oil circulation. It provides 90% better protection against sludge.DD

The oil pick-up tube screen is virtually free of sludge.
Dvs. AMSOIL OE Motor Oil
DDBased 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.
Signature Series Neutralizes Acids
AMSOIL Signature Series is fortified with a heavy treatment of detergent additive and it delivers 30% more acid neutralizing powerE than Mobil 1,* and 36% more than Royal Purple,* helping engines to stay cleaner, longer.

EBased upon independent testing of Mobil 1 Annual Protection 5W-30, Royal Purple High Performance 5W-30, Schaeffer’s Supreme 9000 Full Synthetic 5W-30, Royal Purple High Performance 5W-30, Pennzoil 5W-30, Pennzoil Platinum Full Synthetic 5W-30, Valvoline Conventional Daily Protection 5W-30, Valvoline Full Synthetic Modern Engine 5W-30, Lucas Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896. Oils purchased 05/03/18
Signature Series Helps Keep Valves Clean
AMSOIL fights volatilityU 38% better than Mobil 1* and 17% better than Royal Purple,* helping reduce oil consumption and keep valves clean.

UBased on independent testing of AMSOIL Signature Series Synthetic 5W-20, Mobil 1*Advanced Synthetic 5W-20, Royal Purple* High Performance Synthetic 5W-20, Valvoline* Advanced, Pennzoil Platinum*, Valvoline* High Mileage, Mobil 1* Annual Protection, Schaeffer’s* Supreme 9000, Lucas* Oil, Pennzoil (conventional) and Valvoline* Daily Protection (conventional) in ASTM D5800. Oils purchased October-November 2018.
Keeps Pistons Cleaner
Even after doubling the length of the industry-standard test, AMSOIL delivered 40% cleaner pistons than required by the standard.FF

FFBased on independent testing of AMSOIL Signature Series 5W-30 in the Sequence IIIH Engine Test (ASTM D8111), required by the ILSAC GF-6 and API SP specifications.
Trusted by Professionals
Dedicated engine builders and mechanics put in long hours honing their craft. These architects of powerful, high-performance engines turn to Signature Series to protect their passion.
Hear what they have to say.
Signature Series 5W-30 Synthetic Motor Oil
SDS
Download the SDS
Data Bulletins
Download the Data Bulletins
WARRANTY
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Signature Series 5W-30 Synthetic Motor Oil
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Great oilBy  LUIS,  a  Verified Buyer  from  Perris, California  on  February 27, 2021I put it in my Toyota Tacoma, it made a big difference went i was towing my travel trailer. I will not go back.Bottom LineYes, I would recommend this to a friend.
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Full Synthetic Motor OilThe motor oil I recently purchased from AmsOil was 0W-30. It does a great job keeping the vehicle engine alive and running nice and smooth. I have had absolutely no issues once I started using AmsOil motor oil in my vehicle. Strongly and definitely recommend using their motor oil and their products in general!!!Bottom LineYes, I would recommend this to a friend.
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Bottom LineYes, I would recommend this to a friend.
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Excellent OilVery good oil. Use it in my 2016 Honda Pilot..along with 5 other vehicles and generators. Mileage went up. In addition, I changed over to Amsoil Transmission fluid. Car runs like a top. I recommend this oil with no reservations.Bottom LineYes, I would recommend this to a friend.
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4RunnerTotally impressed with the Signature Series Oil! I did change it at 15k because I wasn’t sure for my first oil change. Glad to say it could have gone another 10K!Bottom LineYes, I would recommend this to a friend.
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Best on the marketOnly oil I use. Best on the market.Bottom LineYes, I would recommend this to a friend.
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Best engine oil you can buy.By  sam,  a  Verified Buyer  from  Phoenix, Arizona  on  February 25, 2021Best engine oil you can buy. It holds up to the heat during summer when it's 110 degrees in Phoenix. Switch to Amsoil Signature Transmission fluid as well. My Infiniti G37 runs 30 degrees cooler and getting 4 more MPG's with both engine and transmission fluid from Amsoil. WHY would you not switch???Bottom LineYes, I would recommend this to a friend.
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Bottom LineYes, I would recommend this to a friend.
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Signature Series 5W30I have been using this product in my GM products requiring DEXOS oil for a decade. The performance has been phenomenal, especially in a GDI engine with fuel dilution where wear metals were consistently kept in the normal range.Bottom LineYes, I would recommend this to a friend.
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Why I use AmsoilI have a fleet of 10 vehicles and growing. I use E-350's and transits. Each vehicle puts on around 2 to 300 miles per day. The amsoil keeps the engines running quiet and I don't have to change the oil every month. I have one van with 430,000 miles and you can't hear it run. Love the product and highly recommend it.Bottom LineYes, I would recommend this to a friend.