It has been my experience that the service department didn't care (or even know) where the car was purchased. It is my understanding that sales and the service / parts departments are separate business units. I've never had any problems or questions related to where I purchased the car. For this purchase, since I'm buying from a dealer within 30 miles of my home, I plan to use their service department. However, if they are idiots, I'll go to another dealer. I have about 6 to choose from within a 30 mile radius.