Steel panel composition
Doors from that era are almost always steel sectional panels on torsion springs mounted above the opening, not the side-mount setups you'd find on an older barn-style door or the insulated composite panels that came standard after the 2000s. After close to forty years, the springs on these original setups are well past a normal service life, and the openers - if original - are chain-drive units with none of the safety-reversal sensors that became standard later.

