Noises coming from rear
 

I'm sure its something simple but i just can't figure it out. There actually 2 things.

One has to deal with the slp loudmouth exhaust. Since the reck and the dealer put her back together, the exhaust has been making a really bad rattling sound. I dunno what it is any suggestions?

2nd when i make turns fats than 20 mph in the car there is a really bad squeaking sound coming from around the back rear well area. Liek i siad its probably something easy but I can't figure it out. I know its not the break b/c they are perfect and most times the break isn't applied when it happens anyways. Any suggestions would be helpful