I have been using K&N filters in all my engines for almost 20 years and have never had any problems with them internal engine components. In combination with a synthetic quality oil like Mobile 1, the oil comes out clean after several thousand kilometers. My new cars only recommend a change every 10,000 miles, which seems like too long to me. However, I have changed the oil and filter at around 7500 miles, even on vehicles that recommend more frequent changes. Even with my 4Runner, which hasβ¦