Thanks again, Klaus.

We bought the car last summer from a Volvo dealer not far from here. It was a trade-in and appeared to be in really good shape. The car fax was clean and I could see that the same person owned it from new. They had an invoice listing what they did in the back shop in prep for resale. It said they put in Castrol Syntec Blend. So when I changed the oil I went with the same. Not knowing for sure what has been used for the first 72,000 miles, my thinking was to go with the blend for the first few changes, then maybe convert to full synthetic. I may even wait until it's almost timing belt time to convert, that way if one of the front end (excuse me - RH end) seals start leaking, I will have to go in there anyway to R&R the belt and replace the seal(s) at the same time.

BTW - my numbers in the original post were a bit off: Purchase at 72,000; First oil change at 75,800; second oil change at 79,445 (today).

My wife does a lot of short-haul driving in it so I feel compelled to change the oil fairly frequently. If I do go full synthetic maybe I'll stretch those intervals somewhat.