Extension Systems: Better For DIY Types

Garage door cables on extension systems are simpler to replace, but some caution should still be used. Here, the springs, which are mounted parallel to the track, pull a pulley backward to provide lift for the door. When the door on these systems is in the raised position, it is fairly easy to remove the load from the garage door cables. When working on extension systems it is important to secure the door in the raised position before releasing the spring's tension: This keeps the door from crashing down unexpectedly and will make your project go much more smoothly. A pair of "C" clamps secured below the bottom roller is a great way to keep the door in the raised position for this work. Just like in torsion systems, these garage door cables should be checked regularly for kinks and frayed areas. Another area to check with extension systems are the pulleys, as these can see wear from repeated use.

Keeping your garage door cables in tip-top shape is pretty straightforward. Replacing them, however, is a bit more involved and depending on your system, should be performed by experienced professionals. Your job, as chief inspector, is to monitor your garage door cables for signs of wear. Most systems are well designed and should provide many years, if not decades, of trouble-free service.

Source: http://www.networx.com/article/maintaining-garage-door-cables