What to Check
Start at the brackets holding the track to the frame - the ones near the top where the horizontal rail meets the vertical section. In homes from this 1968-2000 stock, these are usually bolted into wood framing that's shrunk slightly over the decades, so the bolts can be snug-looking but not actually tight. Grab the track and try to rock it. Any movement at all is your answer. Next, look at the rollers themselves. Original steel rollers from this period are noisy and prone to chipping; if you see a flat spot or a crack, that roller is what's walking the door sideways. Check that the two vertical tracks are parallel - measure the gap at the bottom and again at the top. More than an eighth-inch difference means the door is already running crooked before it even jumps. Last, look at the cable on the side where the door is drifting. A frayed or slightly stretched cable pulls the door unevenly every single cycle, which is often the root cause that gets blamed on the track instead.
When It Stops Being a DIY Job
Tightening a loose bracket bolt is fine to do yourself. Once the door is actually off the track - sitting crooked in the opening, or a roller has come out of the rail entirely - stop. The door is under spring tension, and a torsion or extension spring from a house built in this era is old enough that nobody can tell you from the outside how much life is left in it. Trying to force the door back onto the track by hand while it's under that tension is how fingers and hands get hurt. If the track itself is bent, not just loose, it needs to come off and get reset or replaced - bending it back by eye usually leaves it just straight enough to fail again in a month. We don't recommend trying to re-tension a cable yourself either; that's a ten-minute job for us and a trip to urgent care for most people who try it without the right bar.
