Two years ago the local dealer up here charged me $69.99 to do an oil change on my 6.4L truck. This truck took two more quarts of oil and used a more expensive oil filter than the 6.7L engine does. I guess it depends on the area you live at though. My first oil change on my 6.7L truck was free courtesy of a warranty turbo replacement!

And I also advocate changing your own if it makes financial sense to. Not always the case I guess...my wife's Toyota requires full synthetic oil and with the oil and filters from Wal-Mart it would cost me $46 to change. The Toyota dealer charges $49.99 and includes a car wash with the service, so it makes no sense for me to do it myself.