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.
Fig 1: Checking Ends Of The Diaphragm Spring
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Wear up to half the thickness of the diaphragm spring is permitted.
NOTE:
When performing repairs always match up clutch pressure plate and clutch plate by checking engine code.