His rear bearings have gone (the old loose bearings) and clearly one option is to replace the loose bearings which is what I've recommended him to do and pack with grease.
He likes spending money though!
So, as there's still very limited road disc wheels around on the web I wondered if a MTB 29er will just drop in or do we need to watch out for hub width / freehub compatibility / rim width ?
It's fitted with Avid / SRAM hydraulic
hub width may be a problem - any idea what his is currently (my guess is that hybrids are mtb-sized anyway)
otherwise, yeh - I've done it with a 'cross frame
Mtb wheels will be 135 oln and hybrids can be either 135 or 130 like a road bike
It's the width between the rear drop outs , but easy to measure
I've used my 29er wheel in my surly lht with no issues