Crooked Garage Door: Why It Happens & How to Fix It

The low side tells you which cable failed. Lift cables fray quietly where they flex over the drum every cycle — a few strands at a time, for years — and road-salt corrosion speeds it up on waterfront streets and snow-belt driveways. A cable that has stretched but not snapped lets its side sag; the moment it lets go, the corner drops for good. Last February a Scarborough homeowner sent photos of a fourteen-foot double door hanging low on the left: the cable had worn to a third of its strands and was caught before the panel cracked — a one-visit fix instead of a cable-and-panel job. Cables are matched wear items; the durable repair replaces the pair.

Low corner on the failing side · frayed strands near the drum

On a two-spring door, both springs are supposed to share the lift equally. When one is wound tighter than its twin — or has already snapped its coil — its side rises faster and the door racks crooked in the opening. It's the classic signature of doors past the ten-year mark still running their original springs: one spring quietly fatigues ahead of the other. The balance test below shows which side is weak; the fix replaces the pair and re-balances the door so the lift is even again.

One side rises faster · gap in one coil · door heavy by hand

A bend in the vertical rail pulls that side's rollers out of plumb, and the door racks as it travels. Common culprits: a shovel handle leaned against the track, a slow reverse into a half-open door, or a door that was forced while already crooked — the lean itself bends the track. Light bends straighten on-site with the door secured; a creased section is replaced. Either way it's the one cause that worsens even with the opener unplugged, because every hand-opening drags rollers through the kink.

Rollers bind at the same height · visible kink or scrape marks

One seized or shredded roller drags its side of the door while the other keeps travelling — the door arrives crooked at every stop. Steel rollers wear flat spots; nylon ones crack with age; both fail faster once a track bend starts forcing them sideways. Roller sets are replaced together, and because the technician is already in the cables and drums, worn rollers and frayed cables are usually handled in the same stocked-truck visit.

One side drags · grinding or wobble at one height

Backing into a closed door, a basketball backboard shifting in storage, a delivery van clipping a half-open panel — impact racks the whole assembly out of square in a way hardware wear never does: bowed panels, shifted track, sometimes a cracked stile along the impact line. It's the one cause that usually needs panel scope as well as hardware, which makes the before-you-call photos below matter most here: they show a technician immediately whether the fix is hardware-only or a section replacement.

Fresh dents or cracks · damage lines up with the lean