I’m getting quite a harsh grinding noise from the bearings of my giant p-xc rear wheel , are they worn or are they naturally noisy ?

They’ll be needing some loving by the sound if it

Naturally noisy, they actually use a special grease in them that is full of grit. If any pitting appears on the race of the bearing the grit in the grease will soon smooth it out during normal use. Genius really.

It’s in need of a coat of looking at. Eventually, that grease c/w grit that Hexhamstu refers to, just won’t cut it.