I would stay at 5,000-5,500 miles. Cost of doing business with a small GDI turbo. In Minnesota and short tripping in 10F -20F, I change my Hyundai 1.6T out at 3,000-3,500. Rough service is 3,750. At least you burn off more of your fuel dilution then I do in AZ. I still have `some soot, and want a healthy timing chain at 75,000+. Cost of owning a small GDI turbo.