Garage door crooked or sagging on one side?

A garage door is built to rise and fall level. Two lift cables and the springs share the weight, one on each side. When one side lags, the door tilts, the rollers bind, and the opener strains to drag it along. The tilt is the symptom. The cause is almost always one of a short list, and it's worth knowing which before you press the button again.

Stop first, then look

If the door is visibly crooked, don't keep cycling it with the wall button. A tilted door can wedge in the track and bend it, and the opener may push against a bind it can't win. Disconnect nothing, force nothing. Keep kids, pets, and cars clear, and look at the door from a safe distance.

The usual causes

1. A lift cable off its drum or snapped. The cable runs from the bottom corner of the door up to the drum at the end of the spring shaft. If it slips off or breaks on one side, that side drops while the other still lifts. This is the classic cause of a crooked door.
2. A worn or broken roller. A roller that has cracked or fallen out of the track lets that corner sag or catch. See off-track & roller repair.
3. A loose or bent track. If the track brackets have worked loose from the wall, the track can shift and pinch the door unevenly. Our guide on off-track doors covers what that looks like.
4. Springs that no longer match. When a spring weakens or breaks, the door stops being balanced. A door that sags when open or feels heavy is a clue. You can read about the balance test and the signs of a broken spring.

Why a crooked door gets worse fast

An uneven door puts all the load on one cable and one set of hardware. The opener then pulls the door against that bind every cycle, which can bend the track or damage the opener's drive. What starts as a cable repair can grow into track and panel damage if the door keeps being run. That's why the cheapest move is to stop early.

What a repair usually involves

A technician will check the cables, drums, springs, rollers, and track together, since one failure often hides another. Depending on what's found, that may be a cable repair, new rollers, a re-set track, or a spring replacement. If the door has been run crooked for a while, panels can crack too; see panel replacement.

Where DIY ends

Cleaning the track and checking for a loose bracket is fine. Anything touching the cables, drums, or springs is a job for a trained technician with the right winding tools. When you call, you get a free estimate anywhere in the Grand Rapids metro, and you hear the price before any work starts. Related: repair or replace?