Not everyone understands the importance of regular oil changes. My neighbor had no clue. As long as there was oil in the engine, all was right with the world. Several thousand dollars later, my neighbor learned a lesson we all should know: the oil and filter need to be changed at least three times a year. Preventing engine damage is not the only reason to have the oil and filter changed regularly. There is the matter of enjoying better mileage along with reducing wear and tear on the moving parts. The bottom line is that if you want to make sure the car will go when you want, changing the fluids and filters is essential.