I have a 2004 HCH with a 5 speed. I change the oil every 5K miles and the filter every other time. If in doubt about changing the oil filter every other time, at the next oil change let the old filter drain several hours then cut it apart and inspect the filter elements. My guess is there will not be much if any grit or sludge in the element. Let the next filter go two oil changes then cut it apart and inspect it. You probably will not see a difference.