A door sitting crooked, with rollers out of the track on one side or a lift cable hanging loose, is unstable. Don't open or close it, and keep people and cars clear until it's secured.
Common causes
- A car or bin bumping the door or track
- A cable fraying at the bottom bracket and snapping
- A spring breaking so one side drops faster
- Loose track bolts or worn rollers
What a proper fix includes
Putting the rollers back in isn't enough. The technician should find out why the door came off, replace any frayed cable (usually as a pair), check that the cable drums are wound evenly, straighten or replace bent track, and rebalance the door. Bottom brackets hold cable tension, so leave them to the pro.
How to tell what you're looking at
- Cable off the drum: at the top corner, the cable has unspooled from its grooved drum and hangs loose. The door often sits lower on that side.
- Snapped cable: a frayed end hangs from the bottom bracket or drum.
- Rollers out of the track: one or more rollers sit outside the channel. The track may be bent or pulled away from the wall.
- Door jammed partway: it stops and won't go further either way. Don't force it with the opener.
Why the opener makes it worse
An opener keeps pushing or pulling until its force limit trips. On a door that's off track, that can bend panels, crack the top section where the opener arm attaches, or kink the track further. Unplug the opener as soon as you notice the door sitting crooked.
What happens on the repair
The technician secures the door first, usually by clamping it to the track so it can't move, then relieves spring tension if a cable has to be replaced. They reseat the rollers, straighten or replace bent track, install new cables wound evenly on both drums, re-tension the springs, and test the balance and travel. If a car hit the door, they'll check the bottom panels and struts as well. Ask them to point out anything that caused the failure, like a loose track bolt or a worn roller, so it doesn't repeat.
Preventing it next time
Most off-track doors come from impacts, worn rollers or a cable that frayed slowly. Watching the door run every few months, and calling about frayed cable early, is far cheaper than an emergency.
Rollers: the overlooked part
Many off-track calls start with worn rollers. Older rollers with exposed bearings wear unevenly, wobble in the track, and eventually pop out under load. When a technician has the door apart anyway, it's a good time to ask whether the rollers should be replaced. Quieter sealed-bearing rollers are a common upgrade. You don't have to take it, but it's cheaper to decide while the tech is already there.
When a car hits the door
Backing into a closed or half-open door is one of the most common causes of off-track damage. Besides the track, check for bent bottom sections, a cracked bottom bracket and a twisted strut. Take photos before anything is moved, in case you file an insurance or auto claim. Your insurer can tell you whether it's covered.
Questions to ask
- What caused it to come off track?
- Are both cables being replaced?
- Is any track section being replaced, or just straightened?
- Are the panels damaged, or only the hardware?
Cable drums, briefly
At each end of a torsion spring bar sits a grooved drum, and the lift cable wraps into its grooves as the door rises. If the cable jumps a groove or unwinds, that side of the door lifts unevenly. That can be enough to twist the door out of its tracks. Re-winding a cable onto a drum is done with spring tension safely released, which is why it belongs to the technician. Ask them to check that both drums are tight on the bar and that the cables are the same length.
What a finished job should look like
When the work is done, the door should run quietly through a full cycle, sit level on the floor, and show the same gap from the track on both sides. The cables should be snug, with no slack when the door is closed. If you see any of these problems within the warranty period, call the provider back rather than living with them.
Common questions
Can I pop the rollers back in?
Not recommended. With the cables and springs under tension, a door that comes off the track can shift without warning.
Should both cables be replaced if only one snapped?
Commonly yes. They've worn equally, and replacing both keeps the door lifting evenly. Ask the provider for their reasoning.