ABS and brake warning light both intermittently turn on?

When I apply my brakes in reverse there is a horrible grind but not the normal brake pad grinding like when brake pads need replaced or are dragging, it's a much bigger grinding noise. It started suddenly out of nowhere and I believe it is coming from the front underneath. Everything is normal and fine when backing up until I apply the brakes. This does not happen any other time. Shortly after hearing the grinding noise, I began to hear a raddling noise from under my truck that seemed to get louder or worse. The raddle seems to come from the front underneath area. (Cannot hear it when only back window was down. Can hear it very well when only the front window is down) The raddle noise only happens while driving or in motion. Don' know if noise continues after gaining speed my truck is modified to be a loud running vehicle. So not being able to hear the raddle at higher speeds is not necessarily because it isn't making the noise. It could just be that's its being drowned out by a louder noise.
both front rotors, brake pads, brake calipers all that have been replaced and are brand new. Also, both front CV axles have been replaced. Already checked transfer case and it's full. Just had a complete changing of all vehicle fluids and air filter dash filter all that stuff Oil Stop does. My truck does have two separate lift kits on it with a modified exhaust system. Oh, and the battery is new.