How to tell it is the rollers or the track
You can usually tell a roller or track problem by how the door moves:
- Sticking. The door stops part-way and needs a shove to carry on.
- Dragging. It feels as if the door is sliding on its frame rather than rolling.
- Grinding. A rough, gritty noise as the door moves along.
- Jumping off the track. The door lifts out at one end or drops out of its guide.
- Heavy to push. A door that used to glide with a finger now takes both hands.
What causes it
- Worn or broken rollers. Rollers carry the full weight of the panel. Their wheels wear flat, the bearings seize or the housing cracks, and the panel sinks onto the track.
- Debris. Sand, leaves, pet hair and grit collect in the bottom track and are crushed into it every time the door moves.
- A bent or worn bottom track. Something heavy dropped or dragged across the track dents it, and a door run for years on failed rollers wears a groove along it.
- The building settling. As a house settles, the opening can move slightly out of level, and a door that fitted perfectly starts to run downhill or bind at one end.
What the repair involves
- Lifting the sash. The panel is lifted up into the head of the frame, swung out at the bottom and set down safely.
- Replacing the rollers. The old rollers are taken out of the bottom of the panel and new ones of the right size and load rating are fitted.
- Straightening or capping the track. A dented track is dressed straight. A track worn too far is fitted with a cap, a new running surface over the old one, so the rollers have a true, smooth line again.
- Adjusting. With the panel back in place, the rollers are set for height and level so the door runs evenly and meets the frame square.
The result is a door that moves easily with one hand. If the door slides well but will not close or fasten properly, the problem lies elsewhere, and our page on locks, handles and glass on sliding doors covers it.
Keeping tracks clean
- Vacuum the bottom track every week or two, more often if the door opens onto a garden or a pool.
- Use a stiff brush or an old toothbrush to lift packed dirt out of the corners.
- Wipe the track with a damp cloth and let it dry.
- Do not oil or grease the track. Oil catches grit and turns it into a grinding paste.
- Keep mats and rugs clear of the track so they do not drag dirt into it.
Repair or replace?
Roller and track work is one of the most cost-effective repairs on any door, and it almost always beats replacing the door. A new door is only worth considering when the frame itself is bent or the panel is damaged beyond its running gear. For sliding doors in wood or steel, see sliding door repairs.