I just recently purchased a 2000 A6 2.8 Quattro and within the last day or two whenever the AC is on and not in Econ mode the auxiliary fan rattles and vibrates fairly severely. Is this a sign of it going bad and needing replacement or is it loose and just needs to be tightened?

Thanks

 

just check it and make sure it is clear from touching any thing. it would seem to me like this is a normal finding. pop the hood turn un the engine and AC, pay special attention te the quality of sound it produces if it feels like it is rubing on something

 

It is a rattle that shakes the whole car and can be felt in th cabin. It was not doing this a week or so ago. It seems like a bearing is out or worn and thus vibrates. Is there a way to maybe oil the bearing(s) in this fan without removing it?

 

you are advise there fore to change it rather than lubricate it cuz if it is as described, i doubt if lubricating will solve the longer term prob which may ultimately lead to your revisitation of the prob