Oil should be changed in the interval specified in the vehicle's owners manual. Among 2013 model vehicles, the oil change intervals can vary from every 7,500 miles in some cars to as high as 15,000 miles in others. These are high intervals are because of advancements in oil and vehicle technology.
The actual oil change interval for a car depends on the type of oil used and the conditions under which the car is driven. Vehicles driven in severe conditions require more frequent oil changes than vehicles driven normally. Switching a vehicle from conventional to synthetic oil increases how long the car can go between oil changes, since synthetic oil is more stable at higher temperatures and load. The 3,000-mile oil change interval is largely a marketing ploy used in the service industry to ensure that their customers bring their cars in to the shop. Longer intervals between oil changes are possible because of improvements in oil technology that allows oil to resist breaking down. Advancements in manufacturing techniques also allows for the moving parts of the engine to be machined more precisely than before, reducing the friction between the parts and thus reducing oil wear. Changing a vehicle's oil at around 3,000 miles instead of 5,000 miles than required costs approximately $369 extra per year as of 2014 and wastes 15.2 quarts of oil.