Porsche 996 TT, Repair Manual

Page: 1395 / 2099

Evaluating the cracks on the gray cast iron brake discs
The brake discs must be replaced (as a precautionary measure), if the perforation crack length is over
5 mm (as there is no mileage reserve in the event of further extreme load) or / and the friction plate
rim is torn (lessens smoothness of braking and increases the liklihood that a disc will break)! •
In the evaluation of damage, the following drawings must be used! •
A. Corresponds to a disc exposed to above−average load.
Need not be taken out of the vehicle! •
B. In parts, perforation starter cracks over 7 mm long. Conditions after shock braking 1,200 times (minimum
desired: shock braking 200 times).
Brake disc can no longer be used! •
C. Brake disc with torn friction plate rim −arrow− .
Brake disc can no longer be used! •
einordnung
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