I am getting an extremely loud, heavy, metal sound sometimes as I'm brakeing or coming off the brake pedal. It almost sounds like the whole underside of the car is going to fall off. Any thoughts?

check all the brake pads, take them off and look at them they may need changed.

A heavy metal sound...hmm...would that be a Metallica sound? HA...better than a boy band sound...YUCK! Sorry, very tired from a week at SEMA and trying to deal with a move from there. Got home today and to my new house and nothing went or is going as planned. I think I need a drink...

Yah, sounds like your pads are shot...give em a look-see.

CME