Garage Door Cable Came Off the Drum: Is It Safe to Use the Door?

No. If a lift cable has come off its drum, stop using the door right away. That cable is one of two that carry the door's weight. With one side slack, the door is lifted unevenly, so it can twist in the track, jam, or drop suddenly on the loose side.

Pressing the remote again is the most common way a small problem turns into a bent door and damaged track. Unplug the opener, keep everyone away from the door, and call for garage door cable repair.

Most residential doors with torsion springs have a metal bar above the door with a spring on it and a grooved drum at each end. A steel lift cable runs from each bottom corner of the door up to its drum. As the door opens, the spring turns the bar, and the cables wind neatly into the drum's grooves. As it closes, they unwind.

When a cable "comes off the drum," it has jumped out of those grooves or unwound completely. The door may still move, but that side is no longer controlled. Because the whole system is under heavy spring tension, a loose cable can whip or bind without warning. Doors with extension springs along the tracks use cables and pulleys instead of drums, and a cable that slips off a pulley carries the same kind of risk.

A cable almost always comes off because it went slack. When it loses tension, there is nothing keeping it seated in the grooves. These are the usual reasons.

• A broken spring, which leaves the cables with no tension behind them
• The door closed on an object, so it stopped while the drum kept turning
• A worn or frayed cable that stretched or started to come apart
• A roller out of the track, which lets one side of the door hang or tilt
• Loose drum hardware or a drum that has shifted on the bar
• A worn bottom bracket where the cable attaches to the door
• An impact, such as a car bumping the door

You may hear a loud snap or bang, or a grinding noise as the door moves. More often, you see it. Look for a cable hanging loose beside the track, a door that sits lower on one side, a door that stopped partway with a crooked bottom edge, or a gap between the door and the track on one side.

Also look at the spring above the door from a safe distance. If there is a visible gap in the coil, the spring has broken, and that is likely why the cable came off. Some LiftMaster and Chamberlain openers have a cable tension monitor that reports code 3-5 when it detects a cable problem. Our guide to opener error codes explains that code.

Your goal is to keep the door from moving until a technician can secure it. Do only the following, and nothing that involves touching the cable, drum, spring or bottom brackets.

• Stop pressing the remote, wall button or keypad
• Unplug the opener so nobody can run it by accident
• Do not pull the emergency release cord; the door could drop
• Keep children, pets and cars away from the door
• Do not try to lift, push or lower the door by hand
• Take photos from a safe distance to show the technician
• If a car is trapped inside, say so when you call

Resetting a cable means working against the full tension of the spring system. The cable, drum and bottom bracket all hold stored energy, and a tool that slips or a cable that releases can cause serious injury. On a crooked door, the panels and track may also be under strain that is hard to see.

There is also the question of why the cable came off. If a spring broke, the door needs broken spring repair at the same time. If the door came out of its track, the track and rollers need attention too, which is part of off-track repair. Putting a cable back without fixing the cause usually means it comes off again.

Lift cables are bundles of thin steel strands that bend around a drum or pulley every time the door moves, so they wear with use. Moisture speeds that up. In humid places, cables rust slowly along their length. In cold places, salty slush from cars soaks the bottom of the door, where each cable attaches to its bottom bracket, and that end often rusts first. Our Cleveland garage door repair page covers how road salt wears down doors there.

Look at the cables from a distance now and then. Broken strands, rust, kinks or a flattened spot near the bottom bracket are signs a cable is wearing out. Don't touch or tug on them. A worn cable is a reason to schedule a repair before it lets go.

Yes. Many commercial sectional doors use the same drum-and-cable system as a home door, only larger and heavier, and they cycle far more often. A cable that comes off on a loading dock door can leave a business unable to ship, receive or secure the building. The same rule applies: stop using the door, keep people clear and have the cause found. Our commercial garage door repair page covers sectional, rolling steel and dock doors.

You can't safely adjust cables yourself, but you can avoid the conditions that leave them slack. Most of these habits take a few seconds.

• Keep the door's path clear so it never closes on a bin, bike or car bumper
• Stop using a door that sits uneven or travels with a jerk
• Listen for new grinding, popping or snapping sounds
• Rinse salty slush off the bottom of the door in winter
• Have the cables checked during regular garage door maintenance
• Replace worn springs before they break

A technician first secures the door so it cannot fall, then finds the cause. That means checking the springs, both cables, both drums, the bottom brackets, the rollers and the track. Cables wear together, so if one is frayed, the other is often close behind, and replacing both is common.

After the repair, the door should be balanced and run through several full cycles, with the opener's auto-reverse and sensors tested. If the door is stuck open and your home is not secure, ask about emergency garage door repair. We will give you the price before any work starts.