Parking Brake and braking vibration on 2007 Chevrolet Impala

When Parking brake applied car will not move forward even in drive but car will roll backwards easily when parking brake applied also seperate problem car vibrates when braking at higher speeds or coming to a stop at a sign brakes seem to grab and let go rythemicly

1 answer
The vibration problem is caused by faulty rotors. Having your disks (rotors) milled will fix this problem.