A survey by CalRecycle finds almost 10 million Californians still change their motor oil every 3,000 miles or less. But CalRecycle's Mark Oldfield says for most cars that's a waste of oil.
Mark Oldfield: Today's cars and today's oils allow us to go further than that in many cases, and many manufacturers now recommend 5,000, 7500 or even more miles between changes. (0:10)
Some newer Ford, Audi and Mercedes models suggest oil changes every 10,000 miles.
Oldfield says by only changing oil according to the carmaker's specifications, Californians could reduce use by more than 20 million gallons a year. You can find manufacturer's recommendations in your owner's manual, or look up the oil change suggestions for your car at CalRecycle's website.