I went through this with my son's car. The accessory drive pulley is rubber mounted to the big bolt. They can separate which is what my son's car did and is probably your problem. Unfortunately the pulley, bracket and shaft are one assembly and can not be repaired. A new Ford part is about $140.00 I think. Lucky for me, I did an engine swap and used motor had one on it so I had a spare. More bad news, that pulley can come off fairly easily but if it doesn't it will be a real PIA. To take it OFF you have to turn it CLOCKWISE. If it does not come off easily you have to use the biggest and baddest impact wrench you can find. It can also come apart where you don't want it to and require cutting the shaft so you can get a socket on the shaft behind that pulley. You can loosen the engine craddle mounting bolts on the passenger side to lower it to give access to the bolt. Good luck and hope yours comes out easily.