New noise from a sliding door almost always means metal-on-metal contact that shouldn't be happening, and it's often the earliest, clearest warning sign before a door gets truly stuck.
Noise often shows up before the door feels significantly harder to open, which makes it one of the best early signals to act on before the issue compounds.
Grinding is a low, rough scraping sound, different from a squeak (high-pitched) or rattle (loose parts knocking). Grinding usually means metal-on-metal contact.
Don't ignore it or just spray lubricant and move on, grinding means something is already being damaged with each use.
Continuing to use a grinding door accelerates wear on the track surface, turning a simple roller swap into a track repair too.
Cost: $180-$320 for roller replacement, more if the track has already been damaged.
Time: 45-90 minutes typically.
Repair. Grinding is almost always fixable without replacing the door.
Sand and grit act like sandpaper inside the track, common in homes near beaches or with a lot of outdoor foot traffic.
Generally yes, grinding indicates actual material wear happening, while squeaking is often just a lack of lubrication.
Light lubrication won't hurt, but it won't stop the underlying wear, get it looked at before the track is damaged too.
Get it looked at early, before it becomes a bigger repair.