The door track on your garage door is actually four separate pieces. There are two vertical pieces and two horizontal pieces that join together with flag brackets on the top of the vertical tracks. Most often the vertical tracks, the ones against the door frame, will receive damage from being hit. Fixing a garage door track depends upon the damage. Tracks that are out of alignment do not require removal. Tracks that have extensive damage require replacement. Replacement track blanks and track brackets are available at garage door dealers and some home improvement stores.InstructionsReplacing the Track1Open the garage door to the fully open position. Unplug the garage door opener if your door uses an opener. Ensure that the bottom roller on the door is above the seam between the vertical and horizontal track. Look on the inside of the track to see the seam between the two pieces. Lock a pair of vise grips on the upper track below the bottom roller.2Locate the two fasteners that connect the top of the vertical track to the flag bracket. The flag bracket is the angle bracket above the vertical track where the horizontal track angle connects. The track attaches to the flag bracket with pop rivets. Drill the pop rivets out of the track and flag bracket with a 1/4-inch drill bit. Do not loosen the flag bracket from the wall. The flag bracket also supports the torsion spring or cable of an extension spring.3Remove the hex head lag bolts securing the vertical track brackets to the wall with a socket wrench. The vertical track has two brackets that attach the track to the door frame between the flag bracket and the floor. If you have a garage door opener, remove the bolt securing the photo-eye sensor to the bottom of the track with the socket wrench.4Position the new track under the flag bracket, lining up the top of the track with the end of the upper track. Attach the track brackets to the wall loosely with the lag bolts, using the existing holes in the door frame. Do not tighten the track brackets all the way.5Insert 1/4-inch machine track bolts into the holes in the top of the track and through the track bracket, from the inside of the track. Secure the bolts from the other side with nuts and tighten the nuts with a socket wrench. The heads of the bolts should sit flat inside the track. Tighten the track brackets to the wall and attach the photo-eye sensor to the bottom of the track.6Remove the vise grips and lower the garage door. Plug the garage door opener back into the ceiling outlet.Realign Track7Close the garage door and measure from the inside edge of the track to the end of the door with a tape measure. Ideal spacing between the two is 1/2 inch.8Loosen the lag bolt securing the track bracket to the wall a couple of turns with a socket wrench. Move the track left or right until you achieve the 1/2-inch spacing. Tighten the track bracket lag bolt.9Place the claw of a hammer over the top edge of any bent track bracket. Twist the bent bracket straight with the hammer. Tips & WarningsDo not attempt to repair the upper tracks. The upper tracks support the tension of the extension springs or the ends of the torsion shaft for torsion springs. Call a professional if the upper tracks are in need of repair.