One problem related to brake disc pads has been reported for the 2005 Mercury Grand Marquis. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Mercury Grand Marquis based on all problems reported for the 2005 Grand Marquis.
Both front inner brakes not properly contacting rotor. Only a 1 inch width of inner brake pads have ever contacted rotor. Based upon the amount of rust and pitting of the non contact area of the rotors it appears that the brake pads were never contacting properly. In all my years of servicing vehicles I have never seen this type of defect before.