Fixing Mirror Rattle The side mirror rattle is a common problem on many of the S197 (2005-2007) Mustangs.  Ford has not acknowledged this problem and if you bring your car to the dealer, most of them don't know how to identify or fix this problem.  This fix was documented by  My77stang on the Mustang Forums .  Some of the pictures on this page were borrowed from other posts on other forums. Although the fix can be performed with the mirrors attached to the car, removing them is fairly simple and the precaution could actually save you some time and agravation if you inadvertently loose a screw, nut or break something. Remove the plastic interior trim piece by pulling it straight out. There are two clips and a couple of plastic alignment pins holding the plastic cover in place. This will expose the 3 mirror mounting bolts.    Unplug the wires going into the mirror (brown plug).  Next, remove the three 11mm nuts to remove the mirror from the vehicle.  Be very careful not to drop any of the nuts into the door. Using a large flat head screwdriver or a similar tool, pry between the mirror and where the mirror mounts to the housing.   This will take some effort, but it will pop off..  If done carefully, this can be accomplished without causing any damage to the mounting tabs (which are circled in the picture to show how the mirrors are attached.) Remove the three torx screws holding the mirror actuator to the mirror housing. This will expose the mounting screw behind the actuators. so that you can access the screw behind it. Tighten the torx screw circled in the picture, this is the cause of the rattle. As a precautionary measure, apply loc-tite or epoxy  to ensure this problem does not recur. Reattach the mirror motor using the screws removed previously. Again, you might want to use some Loctite to keep them from backing out.  Re-attach the mirror by pressing it in place.  Then, reinstall the mirror assembly on the vehicle, attach the three 11 mm nuts, the wiring harnass and the plastic triangular cover.