911 Targa 4S (997) F6-3.8L (2007)
Edge damage on PCCB brake disc
Max. permissible width/depth = 2 mm
Max. permissible length= 10mm
Max. 3 damaged edge areas permissible
Front without PCCB
WM 465002 Checking front brake discs - wear assessment
Brake disc wear assessment - General
The condition of the parts can make replacement necessary under two criteria, depending on the amount of wear on cross drilled (perforated) brake
discs:
1. Cracks in the cross drilled friction plate at advanced stage.
2. Brake disc minimum thickness is not attained due to wear (material erosion due to friction).
In practice, both forms of disc erosion occur.
Normally, brake disc replacement is necessary after the thickness falls below the minimum. In rare, isolated cases (of very high loads for long periods)
replacement may be necessary due to crack formation. To a certain extent, these cracks may be rated as not important. The maximum permitted
perforation crack length is 5 mm.
Perforation crack length is too big (greater than 5 mm)
Checking grey cast iron brake discs - evaluating cracks
No need to remove from the vehicle as the perforation crack length is small (less than 5 mm).