Watching Todd's rebuild video of the super charger (not sure if it's the same as the Turbo Charger), there are needle bearings on the connecting rod and he applies a little grease to the bearing when rebuilding the unit. To me, this would indicate that it's a serviceable unit that is not "sealed", you can remove the connecting rod and add grease if needed. Not sure if that helps, but that's what his video shows.
https://www.youtube.com/watch?v=IylDJ1DDMSQ
at around 28:00 minute mark or so.