For the kind of doors we run into on this side of town - steel sectional, extension spring, early-90s builder track - the truck carries the parts that actually fail on that hardware: nylon and steel rollers in the common sizes, replacement track sections, end brackets and center hinges, and extension spring cable in standard lengths. We also carry the fasteners that go with 1990s framing, since a lot of the failures we see are a stripped screw hole in the jamb rather than the hardware itself giving out.
What we don't carry is every custom track length or an inventory of discontinued panel styles - if your door is an oddball width or the manufacturer stopped making that panel profile years back, matching it can take an extra day to source. We'll tell you that on the spot rather than have you wait around wondering.
For the rest of what the Atlanta crew handles across the service area, the [off-track repair overview](/garage-door-off-track-atlanta-ga) covers the broader picture; this page is about what we see specifically once we're out in Brookhaven.