WARNING: This page is about a different car, the 2005 Audi A4, 2004 Audi A4, 2003 Audi A4, and 2002 Audi A4. However, it is still accessible from the selected car via links, so may be relevant.
Possible damage:
Fig 1: Identifying Of Intermediate Pinion, Drive Pinion, And Pinion Gears
Courtesy of VOLKSWAGEN UNITED STATES, INC.
Faulty spur gear bearings or spur gears - 1 to 3
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