I have a 2007 Chevy Cobalt. I recently replaced the transmission after the vehicle had sit up for a few months. When test driving the vehicle I noticed a roaring sound coming from the front end. The car also has a minor shake when you apply the brakes although they seem to be stopping the car like it should. I did replace the brake pads when I replaced the transmission so i'm thinkng the roaring may be coming from the brakes since it wasn't doing this before replacing the transmission and brake pads. I suspected a warped rotor but the brakes was working fine when the transmission went out. When I got home this evening I noticed both front rotors were very hot. I had driven 20 miles on a 4 lane road so the brakes had not been used much. Is this normal or would the brake pads be dragging on the rotor?