A door and opener installed around 1991 is old enough now that plastic gears in chain-drive openers are a common failure point, and the drums and cables on the original torsion springs have usually seen 25-30 years of cycles. That's past the point where we'd recommend just replacing a cable and calling it done - if the springs are original, the opener is original, and the door is original, it's often cheaper long-term to replace the whole system at once rather than keep patching one part while another fails a year later. We won't tell you to replace a door that's working fine just because of its age, but if you're already calling about one broken part on a 30-plus-year-old setup, we'll be honest about what else is likely close behind it. Winters here call for a door that seals well and hardware rated for cold - lubricant and weatherstripping that work fine at 40 degrees can seize or crack once temperatures drop hard, and that matters for a door and opener already past their expected life.