1996 Blazer LT, just had new brakes all around, rotors and pads, drums and shoes. Now, when braking fairly hard from about 30 mph, I hear a "double clicking" from the rear brakes...almost sounds like a rock tumbling in a hubcap. Remember hubcaps? My mechanic took everything off again, and all seems to be right. The clicking correllates with the speed of the tire rotation...click click..click click....click click......and so on...

 

check for rocks in your tire tread

 

ONLY when braking...I know what a rock or a screw sounds like in my tread...took a rock out tonight when I got home, actually...glad it wasn't a screw. Like I said, it happens when I engage the brakes...

 

Still no idea what's going on with those brakes...I saw another thread where a bad bearing may have the tire not "running true" to the rest of the vehicle...wonder if that could be the cause...or a bent axle...