Supercharger on the 3800 motor rattles?

Answer 1

This is almost always indicative of wear in the bearings that support the ends of the s/c shaft. It is about the only thing that goes wrong with the s/c - which is generally a good unit. Some shops will tell you that you must replace the whole thing - they are either lazy, incompetent or trying to take your money. There are places that will change the bearings on the shaft and it is fairly straightforward to do and not terribly expensive. The only trick is that GM will tell them the bearings are not available. This is when a good shop will take the bad bearing out and source the part themselves from a bearing supply specialist. I know an owner of a well established used car dealership who stocks a few of these bearings all the time and if he gets a s/c 3800 car in, he is all set to do a bearing swap with no fuss and little labour just to be sure his customers are kept happy.