Less than perfect rear brake discs
Some 2010 and 2011 Ford Fusion/Milan/MKZ vehicles built between 12-1-2009 and 10-26-2010 may exhibit a single rear wheel stud fracture. A small number of rear brake rotors may have been manufactured with a wheel mounting face that is not flat, possibly resulting in a stud fracture.
Service rear brake rotors are also affected. Service brake rotors that may not be flat on the wheel mounting face were available from December 2009 through approximately January 2011 and could be installed on prior model year(s) 2006-2009 Fusion, Milan and MKZ/Zephyr vehicles.
Remove the wheel. Clean the rear brake disc wheel mounting surfaces with a suitable wire brush. Position a machinist’s straightedge flat against the rear brake disc wheel mounting surface, with the side of the straightedge next to or touching the wheel hub. Using a feller gauge, check for flatness. If a 0.025-inch (0.64mm) feeler gauge can be inserted between the mounting surface and the straightedge, replace the brake disc.
Using special tool 204-592, remove the broken wheel stud from the hub. Using two large flat washers and a 12 mm x 1.50 nut, install a new stud. Seat the replaced stud using 40-80 ft.-lbs. of torque.