Mobile Oil-Change Service business. Grease those startup gears and launch an oil-change service. Business Overview With more than 130 million vehicles registered in the United States, the future looks very bright for the enterprising entrepreneur that starts a mobile oil change service. Assuming the average vehicle is driven 15 thousand miles per year, and that the oil is changed every 5,000 miles, that adds up to a whopping 390 million oil changes each year in the United...