I run a 300 tdi and have just done a front pad change. Since changing them they've started to rattle around in the caliper making a hell of a metalic clunk every time you hit a bump or brake. Has anyone heard of this happening before? Can calipers wear that much?? I've checked the pads and they haven't been machined incorrectly. Would it have been possible for previous owner to "shim them up" without me noticing?? Any advice would be greatly recieved before I start splashing out on calipers.