The first sign is impossible to miss, since you're sure to notice if you or someone else hits the garage door with a vehicle. Any serious impact can damage the garage door springs and necessitate replacement. Even if you don't see any visible signs that the spring has failed, it's a good idea to have it checked out if the garage door has been hit by something.
Problems Opening or Closing
If your door is having difficulty opening or closing all the way, it may be the spring that is to blame. This is especially true if the door begins to open or close but stops halfway. While this doesn't always indicate a faulty spring, it does mean that there is a problem with the sensors or the opener itself and should be looked at by a professional.
When the spring begins to fail and loses tension, sections of the garage door can begin to sag. When the door opens or closes you may notice that the sides don't go up and down evenly because one side lags behind. Lopsided opening and closing is most likely a problem with tension in the springs, which often means replacement is necessary. You should check your door monthly by disconnecting the door from the opener and manually opening and shutting it. The door should shut at the same rate on both sides, and should be able to stay halfway open without shutting or opening the rest of the way.
An unusually loud garage door is the last indication that the springs should be replaced. Some doors have extension springs that you can see to note any rust or warping on them. However, be sure to call a professional for garage door spring replacement in Marietta because the tension in these springs can make them extremely dangerous for those not trained to replace them.