Time and mileage intervals vary by vehicle manufacturer and whether an engine requires synthetic oil (which is meant to last longer). Use the guidelines in your owner’s manual, including whether most of your driving qualifies as happening in “severe” conditions, such as frequent short trips and stop-and-go driving. Under those conditions, you should change the oil more frequently.
How often should I replace my oil?
You should change the oil at least as often as is recommended by the vehicle manufacturer (the information is in your owner’s manual). These days, that’s every 7,500 to 10,000 miles on many vehicles. Many mechanics recommend doing it more often, such as every 5,000 to 6,000 miles or every six months, whichever comes first. If you do mainly short trips and/or stop-and-go driving, you should change the oil more often. How about every 3,000 miles? Though that’s overkill, it can’t hurt, and it might extend the life of your engine.
Why do I need to change my oil?
Oil is the lifeblood of an engine; it lubricates and cleans moving parts and performs a vital cooling function as it circulates. Over time and repeated exposure to cold starts, short trips and engine heat, oil gets dirty, becomes thicker and loses its ability to prevent sludge and deposits from forming. Mechanics often say that changing the oil is the best preventive medicine for extending engine life.