Can you find what you need in the big home improvement stores? Can they show you how to fix a broken garage spring? Do they know what tools and replacement parts you need? Do they know what safety precautions you need to take? If you have any questions during the project, can you call them for help? Have they ever actually repaired a broken garage door spring themselves?
A garage door spring replacement should cost between $175 and $225 for a single tension spring and between $250 and $300 for two tension springs. Most garage door companies carry a wide enough variety of spring sizes to cover most residential doors. As long as the proper amount of turns are put on the spring, there are more than one correct springs to use for any one door.
10.1 It is now time to wind the new springs, but before doing so, I recommend marking the shaft just beyond the winding cone. This is a final step taken to assure that you have installed the springs on the correct sides of the center bracket. Torsion springs always grow in length when they are wound in the proper direction. If your spring does not get longer as you wind it, you are winding it the wrong direction probably because it is improperly installed. We recurrently get calls about springs coming loose from the cones at about 6 turns. If this happens, switch the springs.