Oil change intervals are controverrial. Lots of opinions. I agree: Run synthetic oil and change the oil filter every 10,000 miles. Regular oil breaks down over time. Synthetic does not. I have known car and trruck owners who never changed their synthetic oil. Even after 200,000+ milles. Just changed the oil filter and added oil as neccessary. I run Euro 0W40 synthetic and change oil and filter at 10,000 miles on my SRT-6 and 2 Audis (per service manuals).