South Whittier's houses cluster around a median build year of 1957, which puts most garages here a decade earlier than the broader Whittier service area's 1964 median. That matters because 1957 is before torsion springs became the standard setup on single-car garages in this part of the county. A lot of these doors are still running on the original extension-spring configuration, or a replacement that copied it, with the springs mounted along the horizontal track instead of over the header. Extension springs stretch and wear differently than torsion springs, and they're the ones most likely to snap a cable or drop a door off one side instead of lowering it straight. The mild year-round temperate band this area sits in keeps the metal from the kind of freeze-thaw cycling that cracks hardware elsewhere, so when a spring or cable fails here, it's almost always fatigue from age and cycle count, not weather damage. That's a different failure pattern than what shows up in newer construction, and it's why a maintenance visit on a 1957 door looks for different wear points than one on a 1980s door a few miles over.