FWIW modern day oils are pretty tough. The more cylinders you have the longer the oil will generally last. For a Volvo car, the standard oil change interval is 7,500 miles. For a VW using VW spec synthetic oil the change interval is 10K miles. If you aren't running a high revving 4-cylinder turbo changing the oil at less than 5000 miles is nuts, unless otherwise stipulated by your warranty.
We change the oil on the VW at 10K miles. Her drive is 99% highway, she uses VW spec synthetic oil, and VW spec oil filters. Change fuel filters in diesels every 20K.