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How do oil and air filters affect your engine?

Author's Note

In the bad old days, when cars required a lot more maintenance -- I'm talking 'bout the 1990s and earlier, here -- we took it as an article of faith that you changed your oil (and oil filter) every 3,000 miles (4,828 kilometers). I believe this was actually a law handed down by the car gods. If you chose to violate their rule, you had to pay tribute to them in the form of hefty engine-repair bills. I learned this lesson the hard (read expensive) way with a beloved but star-crossed Subaru XT coupe, back in my less-responsible youth. Today, thanks to better engine technology, we enjoy a bit more leniency in those filter and fluid-change schedules. With that said, if you appreciate your vehicle's hauling you around from point A to point B, you'll make the minor investment to swap out those filters when the manufacturer recommends. Consider it very cheap preventive care for your car (bonus: your ride will also run better). And best of all: no belief in automotive deities required.

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  • "Car Talk Service Advice: Air Filters." March 31, 2005. (April 15, 2012)
  • Clarke, Warren. "How to Change Your Car's Filters." Jan. 25, 2003. (April 14, 2012)
  • Norman, Kevin; Huff, Shean and West, Brian. "Effect of Intake Air Filter Condition on Vehicle Fuel Economy." Oak Ridge National Laboratory (U.S. Department of Energy). February 2009. (April 16, 2012)
  • Tugend, Alina. "The 3,000-Mile Oil Change Is Pretty Much History." The New York Times. Sept. 10, 2010. (April 17, 2012)
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