Minnesota winters are hard on any garage door, but a 1970s-era door in Anoka takes it worse than a newer one. The service area sits in a cold climate zone with severe winter conditions, and a door built when insulation standards were lower just doesn't hold heat the way a door built to current code does. That means more condensation on the inside face of older steel panels, more rust starting at the bottom seal track, and springs that were sized for a lighter, less-insulated door now straining under a replacement panel that's heavier than the original.
Extension springs, common on Anoka's older stock, also fail differently than torsion springs. They don't contain the recoil the way a torsion spring on a shaft does, so a broken extension spring on an old side-mount setup is a bigger safety problem, not just a bigger repair. If your opener is original to a 1973-built house, it's also likely missing the photo-eye safety sensors required on anything installed or serviced since the mid-1990s, which is its own fix we flag honestly rather than just bolting new springs onto old hardware and calling it done.