First drive back home in the S8 yesterday
I got a bit carried away last night and pulled the alternator off to have a closer look.
It came apart ok and I found out which bearing needs replacing along with the dimensions and part number for a replacement. Just need to find someone that has one now.
I'll be changing the regulator in there too as the brushes don't have much life left in them.
The problem bearing is behind the pulley. I managed to carefully remove the dust cover, clean out the old dead grease and clean out the crap with brake cleaner. Unfortunately the outer race is worn so I refilled it with fresh grease, dust cover and put it back together. It's a little quieter but not much.
Part number: SC03A21LHA.
MG