On the inside of the backing plate is a small window usually covered with a oblong rubber grommet/seal. Pull the rubber grommet off and adjust the star wheel. with a brake adjusting tool is the easiest,( flat blade screw driver might work too) until the e-brake pedal goes a third to half way down and holds good. The star wheel adjusts the e brake shoes closer or farther away from the drum inside the rotor. The rattling you hear "may" be the e brake shoe brake material has seperated from the metal shoe itself. it did on mine and had to buy new ebrake shoes..they are like under $30.00 for the pair
Marauder, Trilogy supercharger, all supporting mods.