"CABLES"
Before you read on about the how to and what to on cables, you might want to familiarize yourself with springs, door balance and lubrication.
The cables on torsion spring set-ups wind up on cable drums. The cables on the extension spring set-up work on a pulley system. On all garage door cables you'll need to look them over carefully to see if there's any fraying occurring. If they are fraying, have them replaced by a professional only.
Some times when one cable starts to fray the door will tilt. As a cable frays it gets longer. Both cables always need to be the same length. If the door starts to tilt or becomes unleveled, rollers can pop out. That would cause the door sections to fall out of the tracks. I've seen doors fall right out their tracks, or hang in the open position by just 2-3 rollers.
Another cable safety check for both spring set-ups is to check the cables when the door is open for any excessive slack. Loose cables can jump off the cable drums or out of the pulleys. Also follow the cable to the bottom bracket. Look to see that the cable loop and bracket are not worn. You're looking for a visible groove mark on the bracket. Some doors can shift and bottom brackets start to rub on the track. Tracks can cut into the bottom bracket. If half your garage door lost tension it could get real ugly.
There isn't much to do to a cable in the way of maintenance. The cables on garage doors near the coasts tend to rust or corrode because of the salty ocean air. With the garage door open you can spray most of the cable on its cable drum with WD-40. On the extension spring set-up it would be a little tricky. THE DOOR MAN recommends either spaying WD-40 directly on the cable with a rag behind the cable or soak the rag first and wipe the cable very lightly. Remember to check for any sign of fraying. A metal splinter does not tickle.
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