Fresh air blower fan replacement

[Vic Norman]

The blower fan on my 1996 A4 started to get rather noisy on a recent trip
when I was using the A/C a lot. Now it's stopped working altogether. A quick
check in the Bentley manual indicates that replacing the fan motor is
relatively easy - which is a change after the hassle I had replacing the fan
in my 100s a few years ago. I have one question - is there any maintenance
(bearings, brushes) that can be done to reuse the existing fan motor or is
it strictly a replacement-only situation?
Thanks. Vic Norman 1996 A4