Garage door cable and drum repair
The lift cables are the two steel ropes that carry the door's weight from the springs down to the bottom brackets. When one frays, snaps or comes off its drum, the door goes crooked, jams in the opening, or drops on one side. We replace cables, drums and bottom brackets across Hamilton, Stoney Creek, Grimsby, Burlington and Niagara.
What a failing cable looks like
The door is crooked in the opening
One side has come up and the other has not. The cable on the low side has either snapped or slipped off its drum. Stop using the door.
A loose cable hanging by the track
Slack cable means the tension that was holding the door has gone somewhere else, usually into a broken spring or a cable that has unwound off the drum.
Rusty or fuzzy-looking cable
Steel cable fails one strand at a time. A cable that looks fibrous or has broken wires standing proud of it is weeks from letting go, not years.
A bang, then the door dropped on one side
A snapped cable under load. The door is now supported by one cable and a spring system that is no longer balanced.
Cables are a counterbalance part, not a DIY part. They are attached to the bottom brackets, which are under the full tension of the spring system even when the door is closed. DASMA's homeowner inspection guidance says to look for loose cables but explicitly not to touch, adjust or repair the springs "or anything to which door spring parts are fastened, such as wood lag bolts, steel brackets, cables, or other like items."
If a cable has failed, do not run the opener and do not try to lift the door by hand to straighten it.
Why cables fail
- Age and fatigue. They flex over a drum on every cycle. They wear out on the same clock the springs do, which is why a cable failure often turns up within months of a spring failure.
- Moisture at the bottom. The lowest few inches of cable sit where water, snow and road salt collect. On this lakeshore corridor that is the usual place a cable starts to rust.
- A door that binds. Anything that makes the door drag, a bent track or a seized roller, puts uneven load into one cable and shortens its life.
- Bad winding. A cable that was not seated properly in its drum groove climbs over itself and eventually jumps off.
- A broken spring left in service. Running a door on a broken spring loads the cables and the opener with weight they were never meant to carry.
What the repair involves
- The door is secured and the spring tension released in a controlled way. This is the step that makes the job a trade job.
- Both cables are replaced. As with springs, they are the same age and have taken the same number of cycles, so replacing one is a false economy.
- The drums are inspected for wear and grooving, and replaced if the cable has been cutting into them.
- The bottom brackets are checked, because a rusted or bent bracket is what tore the cable in the first place on some doors.
- The cables are wound evenly onto the drums, and the door is set level.
- The door is balance-tested and the opener's travel and force settings are re-checked.
Cables and springs, together
If we are already in the counterbalance for a spring job, replacing the cables at the same time costs a fraction of what a separate visit costs later. If the cables are genuinely sound we will tell you and leave them, but it is worth asking when you book.
Do not substitute parts
Cable diameter and length are matched to the door and the drum, and generic hardware store cable is not the same thing. DASMA publishes a data sheet on component substitution for exactly this reason; the short version is that a door is a system and swapping one part for something that looks similar changes how the rest of it behaves.
Source: DASMA Technical Data Sheet #151, General Code Inspection Guidelines for Sectional Garage Doors (PDF). Checked 31 August 2026.