Strange Brake Issue: Maybe ABS?

My '96 T&C, with 108,000 miles, started making a scraping or groaning sound when the brakes are used. It seems to be coming from the front brakes and it is intermittent. I immediately thought it was a worn pad scraping the rotor, but when I pulled the wheels off the rotors were fine and there was lots of pad left. As soon as I put the wheels back on and made a test drive there was no longer any such awful sound, but the next time I drove it it happened again. Now it's good most of the time. Whats happening! -- Matt

You have a sensor failing. A wheel speed sensor.

Thanks for the tip! I'm not too up on minivan wrenching. Is there a way to test the sensor? How much is a sensor and how hard is it to replace? Should I do both the fronts at once? Thanks again. -- Matt