Thus, synthetic oils can be used safely for much longer drain intervals than conventional lubricants. Red Line Oil also recommends long drain intervals of 10,000 to 18,000 miles. You might ask why other synthetic oil manufacturers are not recommending extended oil drains for their synthetics. They are afraid that if they recommend longer drain intervals, they won't sell enough oil - petroleum oil, that is. You see, petroleum oil is their golden goose, and has been for years.
Petroleum oil is where the money is.
With recommended oil drains of only 3,000 miles, many people are changing their oil 5 to 8 times per year. This is a scary thought for large oil companies who depend upon regular oil changes for their business. More often than not, vehicle life is determined by engine life. Less friction, of course, means less heat in the system. And, since heat is a major contributor to engine component wear and failure, synthetic oils significantly reduce these two detrimental effects.