Brakes Make Intermittent Noise

I Get a noise is the Brake System on My 1998 Dodge Caravan. I installed new pads and turned the rotors. Still had the noise. I replaced the back shoes and turned the drums and still get the noise. It sounds like metal grinding, but it doesn't do it all the time. And now the ABS light is starting to come on occationally. Any help you can give would be appreciated.