Royal Purple 51520 API-licensed SAE 5W-20 High Performance Synthetic Motor Oil - 5 Quart, (Model: ROY51520)

This is the best synthetic I've used to date. Slight power gain, engine idles smoothly.

Best oil, high performance, great fit, seals, lasts forever.

De lo mejor. Un poco raro que sea morado pues se confunde con usado pero eso es solo estetico

Best oil out there! Want better gas mileage and higher performance? Use Royal Purple and see for yourself. I use the 5w20 in a 2005 Dodge Ram 1500 with the 5.7 HEMI. It cost more because your getting more in every quart. Try it and like me you won't use any thing else in your car or truck. See Facts that I researched before I started using Royal Purple. Do the research or try it for youself before you lend judgements on items or comments by those who have. Of course, buyer always beware. Research: The racing markets associate outstanding quality and superior performance with Royal Purple®. This reputation has been earned through Royal Purple's® relentless pursuit of lubrication excellence. Royal Purple® formulates the most advanced lubricants available on the market today. Synthetic oils enable Royal Purple® to make superior lubricants; however, it is Royal Purple's noncorrosive, proprietary Synerlec® additive technology that provides Royal Purple® lubricants with their amazing performance advantages. Synerlec® additive technology truly is beyond synthetic. Royal Purple's® Synerlec® additive technology forms a tough, ionic, chemical film on all lubricated parts greatly enhancing the oil's performance. Royal Purple® manufactures a wide range of high performance, synthetic lubricants for every use from top fuel dragsters to the family car, motorcycles, trucks, RVs and boats. Its industry experts are consistently developing products that outperform leading mineral- and synthetic-based lubricants in performance and protection. Numerous independent tests document performance gains by using Royal Purple lubricants. The sampling of results below are categorized by the performance gains reported. [...] Tests Documenting Horsepower (hp) and / or Torque Gains: Just In! - Drag Sport magazine: hp gain of 2.5% D & D Performance Enterprises: hp gain of 1.2%, torque gain of 1.3% Diesel World magazine: hp gain of 3.2% GM High-Tech Performance magazine: hp gain of 10+, torque gain of nearly 12 ft-lbs Oklahoma State University: diesel engine gain of 2.8% hp Sport Truck magazine: hp gain of 5%, torque gain of 12 lb-ft Tests Documenting Fuel Economy Improvements: Diesel World: fuel economy gain of 10% or 1.7 mpg fordtruckworld.com: fuel economy gain of 7.4% or 1.1 mpg North Carolina State University: gasoline engine fuel economy gain of 2.5% to 5.0% and diesel engine fuel economy gain of 1.5% to 3.7% Oklahoma State University: fuel economy gain of 4.4% Test Documenting Reduced Engine Wear: Insight Services: wear reduced by 80% and oil change intervals extended from once per race to every 3 races Tests Documenting Reduced Engine Heat: Longview Inspection: Max-Cycle reduced operating temperatures 24°F - 44°F Tests Documenting Reduced Emissions: North Carolina State University: diesel engine emissions reduced 17%-34% and gasoline engine emissions reduced 29% (city) and 62% (highway) Oklahoma State University: diesel engine emissions reduced 22% [...] [...] I should have included this in the first review.

This is very good quality oil, don't get me wrong. But for this price point, any other API certified synthetic like M1 or Valvoline (etc) is just as good and is easier to get at your local parts store or wallyworld. I think I'll go with RP's HPS formula if I decide to go with a higher performance oil that I can't get locally.