On a door from this era, the warning signs are mechanical, not cosmetic. A door that used to lift with one hand and now takes two is losing spring tension. A loud bang from the garage, followed by the door refusing to open, is almost always the spring itself snapping - and it's loud because thirty-year-old wire under that much tension doesn't fail quietly. Rust streaking down from the spring coil onto the header is moisture getting into a coating that's worn thin after decades of cold cycling. A door that drifts open or closed on its own, or that sits crooked when it's halfway up, points to uneven spring wear or a cable starting to fray on one side. None of these are emergencies you have to solve tonight, but none of them get better by waiting, either.