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AMSOIL Signature Series 5W-50 100% Synthetic Motor Oil
Product code : AMRQT-EA
AMSOIL Signature Series 5W-50 100% Synthetic Motor Oil
Product code : AMRQT-EA
Current price:
$17.99
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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.
- 28% more acid-neutralizing power than Mobil 1.3
- 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 using the ASTM D6891 standard test.
2Based on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
3Based upon independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896. Oils purchased in July 2020. -
We offer easy returns for customers. If your product is unused and unopened, you may return it within 30 days for a full refund of the purchase price. View full AMSOIL Return Policy.
-
We accept Visa, Mastercard, American Express, Discover and PayPal, and provide secure checkout and encrypted payment processing.
About this item
-
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 Improves Startup Protection
AMSOIL provides better cold cranking viscosity, helping improve wear protection for engine components at startup.PP
ASTM D5293 cold Crank (Lower = Better)
AMSOIL Signature Series(5W-30) Royal Purple High Performance (5W-30) Lucas (5W-30) Driven LS30 (5W-30) Red Line High Performance (5W-30) Royal Purple HPS (5W-30) Cranking Viscosity (㎫ —s) 3800 4500 5000 5750 6100 6100 PPBased on independent third-party testing in the industry-standard ASTM D5293 Cold Crank Simulator test as required by SAE J300.
*Trademark 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.
Signature Series Fights Wear
75% more engine protection against horsepower loss and wear.A
Sequence IVA Engine Test - Lower Number = Less Wear
Industry Standard AMSOIL Signature Series 0W-20 Synthetic Motor Oil Average Cam Wear 90 20.28 ABased on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.
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
![Piston damage due to an LSPI event observed during the testing of a competitor's motor oil.]( "Piston damage due to an LSPI event observed during the testing of a competitor's motor oil.")
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
Sequence IIIH Engine Test - Lower number = better viscosity control
Industry Standard AMSOIL 1X AMSOIL 2X Viscosity Increase % 100% 0.1% 49.6% 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.
Signature Series Helps Keep Engines Cleaner
- Fortified with a heavy treatment of detergent additives, delivering 28% more acid-neutralizing power than Mobil 1* and helping engines stay cleaner, longer.LL
- 50% more detergentsD to help keep oil passages clean and promote oil circulation.
- Controls heat and minimizes performance-robbing deposits.
- Superior thermal durability that resists breakdown and keeps pistons clean.
- Provides 90% better protection against sludge.DD
![Oil pick-up tube screen showing it's virtually free of sludge.]( "Oil pick-up tube screen showing it's virtually free of sludge.")
The oil pick-up tube screen is virtually free of sludge.
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.
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 Guards Turbos
Protects turbochargers 72% better than requiredC by the GM dexos1* Gen 2 specification.
![Part from turbocharger.]( "Part from turbocharger.")
CBased on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
Keeps Pistons Cleaner
Even after doubling the length of the industry-standard test, AMSOIL delivered 40% cleaner pistons than required by the standard.FF
![Piston 40% cleaner from using AMSOIL.]( "Piston 40% cleaner from using AMSOIL.")
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.
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star rating
Best oil out thereBy JAMMIE, a Verified Buyer from Florida on July 28, 2026I would say best oil I’ve bought in a long time would recommend to everyoneBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Signature SeriesBy SCOTT, a Verified Buyer on July 28, 2026If any of my gasoline vehicles require synthetic oil 5w-30 signature series is what it gets no matter what the manufacturer says. It’s never let me down and it won’t! Great oil!!Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
BEST OILBy MICHAEL, a Verified Buyer from OHIO on July 28, 2026Best oil on the planet. I run AMSOIL fluids and filters in all my vehicles. 👍👍Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Quality oilBy LOWELL, a Verified Buyer from Florida on July 28, 2026Great customer service, quick shipping and a quality productBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
QualityBy REMI, a Verified Buyer from Odessa tx. on July 27, 2026Very good product quality.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
High Quality OilBy VICTOR, a Verified Buyer from Las Cruces Nm on July 27, 2026⭐⭐⭐⭐⭐ Excellent products! The AMSOIL engine oil keeps my engine running smooth and quiet, and the oil filter is high quality and provides great protection. I’ve had a great experience with both and highly recommend them.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Best Motor Oil EverBy JAMES, a Verified Buyer from Orlando on July 27, 2026Ordered and picked up the same day - could have had it delivered but i was in a hurry. I use it in all my cars and trucks for the last 15 years and I never have to worry about my engines.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
civic siBy ADRIAN, a Verified Buyer on July 26, 2026Just the right amount of oil I need for the vehicleBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Best product to protect your investmentBy DAVID, a Verified Buyer from Chicora PA on July 26, 2026Best product to protect your investment In the long haul HANDS DOWN!Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
5 30 syntheticBy BARRY, a Verified Buyer from Hazletownship Pennsylvania on July 26, 2026Great product and great Customer serviceBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Compare Motor Oil
Data Bulletins-
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.
- 28% more acid-neutralizing power than Mobil 1.3
- 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 using the ASTM D6891 standard test.
2Based on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
3Based upon independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896. Oils purchased in July 2020. -
We offer easy returns for customers. If your product is unused and unopened, you may return it within 30 days for a full refund of the purchase price. View full AMSOIL Return Policy.
-
We accept Visa, Mastercard, American Express, Discover and PayPal, and provide secure checkout and encrypted payment processing.
-
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 Improves Startup Protection
AMSOIL provides better cold cranking viscosity, helping improve wear protection for engine components at startup.PP
ASTM D5293 cold Crank (Lower = Better)
AMSOIL Signature Series(5W-30) Royal Purple High Performance (5W-30) Lucas (5W-30) Driven LS30 (5W-30) Red Line High Performance (5W-30) Royal Purple HPS (5W-30) Cranking Viscosity (㎫ —s) 3800 4500 5000 5750 6100 6100 PPBased on independent third-party testing in the industry-standard ASTM D5293 Cold Crank Simulator test as required by SAE J300.
*Trademark 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.
Signature Series Fights Wear
75% more engine protection against horsepower loss and wear.A
Sequence IVA Engine Test - Lower Number = Less Wear
Industry Standard AMSOIL Signature Series 0W-20 Synthetic Motor Oil Average Cam Wear 90 20.28 ABased on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.
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
![Piston damage due to an LSPI event observed during the testing of a competitor's motor oil.]( "Piston damage due to an LSPI event observed during the testing of a competitor's motor oil.")
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
Sequence IIIH Engine Test - Lower number = better viscosity control
Industry Standard AMSOIL 1X AMSOIL 2X Viscosity Increase % 100% 0.1% 49.6% 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.
Signature Series Helps Keep Engines Cleaner
- Fortified with a heavy treatment of detergent additives, delivering 28% more acid-neutralizing power than Mobil 1* and helping engines stay cleaner, longer.LL
- 50% more detergentsD to help keep oil passages clean and promote oil circulation.
- Controls heat and minimizes performance-robbing deposits.
- Superior thermal durability that resists breakdown and keeps pistons clean.
- Provides 90% better protection against sludge.DD
![Oil pick-up tube screen showing it's virtually free of sludge.]( "Oil pick-up tube screen showing it's virtually free of sludge.")
The oil pick-up tube screen is virtually free of sludge.
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.
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 Guards Turbos
Protects turbochargers 72% better than requiredC by the GM dexos1* Gen 2 specification.
![Part from turbocharger.]( "Part from turbocharger.")
CBased on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
Keeps Pistons Cleaner
Even after doubling the length of the industry-standard test, AMSOIL delivered 40% cleaner pistons than required by the standard.FF
![Piston 40% cleaner from using AMSOIL.]( "Piston 40% cleaner from using AMSOIL.")
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.
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star rating
Best oil out thereBy JAMMIE, a Verified Buyer from Florida on July 28, 2026I would say best oil I’ve bought in a long time would recommend to everyoneBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Signature SeriesBy SCOTT, a Verified Buyer on July 28, 2026If any of my gasoline vehicles require synthetic oil 5w-30 signature series is what it gets no matter what the manufacturer says. It’s never let me down and it won’t! Great oil!!Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
BEST OILBy MICHAEL, a Verified Buyer from OHIO on July 28, 2026Best oil on the planet. I run AMSOIL fluids and filters in all my vehicles. 👍👍Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Quality oilBy LOWELL, a Verified Buyer from Florida on July 28, 2026Great customer service, quick shipping and a quality productBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
QualityBy REMI, a Verified Buyer from Odessa tx. on July 27, 2026Very good product quality.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
High Quality OilBy VICTOR, a Verified Buyer from Las Cruces Nm on July 27, 2026⭐⭐⭐⭐⭐ Excellent products! The AMSOIL engine oil keeps my engine running smooth and quiet, and the oil filter is high quality and provides great protection. I’ve had a great experience with both and highly recommend them.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Best Motor Oil EverBy JAMES, a Verified Buyer from Orlando on July 27, 2026Ordered and picked up the same day - could have had it delivered but i was in a hurry. I use it in all my cars and trucks for the last 15 years and I never have to worry about my engines.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
civic siBy ADRIAN, a Verified Buyer on July 26, 2026Just the right amount of oil I need for the vehicleBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Best product to protect your investmentBy DAVID, a Verified Buyer from Chicora PA on July 26, 2026Best product to protect your investment In the long haul HANDS DOWN!Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
5 30 syntheticBy BARRY, a Verified Buyer from Hazletownship Pennsylvania on July 26, 2026Great product and great Customer serviceBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
