JARblue

Your brake pads were pressed into the rotor when you collided with the vehicle ahead as long as you were holding the brake; the harder you press the brake the harder the pads press into the rotor. Depending on how long this period was and how hot your brakes were at the time, it is easily possible that a large amount of pad material was transferred onto a single location on your rotors creating a high spot and the resulting shake you are experiencing. Properly re-bedding the pads is a good DIY solution or you can pay someone to resurface or "turn" the rotors as suggested above.

__________________