Linden's median household income sits at $77,434, and most of the houses feeding that number were built well after 1990 - later than the mix across the wider Fenton service area, where homes commonly date to the 1950s through 1990s. That later build date usually means galvanized steel track and roller-and-hinge hardware rather than the older wood-jamb, loose-tolerance setups you find in a 1960s house. The failure mode is different: newer track holds alignment better but the plastic-and-steel rollers wear at the stem, and once one roller lets go, the door can walk sideways off the rail on the next cycle. It's less about rust here and more about a part that's simply reached the end of its service life.