I just changed the oil and filter on my '05 XC70. I use synthetic 5W30, and change it every 5000 miles. I didn't realize until I changed the oil and went to record it in the car's maintenance schedule that it had been over a year since the last oil change. I'm driving the car less now, as I retired and drive another car sometimes. So my question is: if I'm using synthetic, does the 5000 miles/six months whatever comes FIRST still apply, or am I OK changing at the mileage interval? Seems wasteful to change more often than necessary, but I also don't want to damage the car by keeping "old" oil in it. Thanks, as always.