http://answers.yahoo.com/question/index?qid=20080509191144AA7B09k If your brakes haven't been serviced before, 40K miles is about the time for replacing pads for aggressive drivers. The pads can last 60K for conservative drivers. You need to replace the rotors if you feel rattling when pressing brakes hard, especially at high speed on high way. If you don't feel anything when stepping brakes, your rotors are still fine. I don't think you need any service on rear brakes for 40K because they wear out much less than front brakes. Mechanics including dealers just cannot wait to work on your brakes because it is so quick and easy money they can make. My 1998 Caravan has over 140k miles and still runs very smoothly.