Test Values/Wear Limits For 981 GT4 - PCCB Brakes (Optional)
Information
The following condition criteria can make replacement necessary depending on the wear of the PCCB brake discs (new generation without indicators in the friction surface):
- Too many damaged carbon fibres in the PCCB brake disc (wear caused by the effects of temperature). Check PCCB brake discs with test equipment for PCCB brake discs WE 1578 while adhering to measuring requirements .
- With this generation of brake discs, checking of the minimum brake disc thickness is no longer necessary .
Procedure for: 46 51 02 Checking front PCCB brake discs (wear assessment using VAS 6813 test equipment)/46 54 02 Checking rear PCCB brake discs (wear assessment using VAS 6813 test equipment).
| Location | Description | Type | Basic value | Tolerance 1 | Tolerance 2 |
|---|---|---|---|---|---|
| Pad thickness, front and rear | Measured value | approx. 12.0 mm | |||
| Pad thickness, front and rear (wear limit) | Measured value | 2 mm | |||
| Brake disc thickness, new (front) | Measured value | 36 mm | |||
| Brake disc thickness, new (rear) | Measured value | 32 mm | |||
| Wear limit of front and rear brake discs | Measuring with VAS 6813 test equipment. Note measuring prerequisites. New values/wear values and three measuring points are lasered onto the brake disc hub. Wear value reached: Replace PCCB brake discs on both sides of the axle. | Measured value | XX/XX Read value on brake disc hub |
||
| Thickness tolerance of brake discs (max.) | Measured value | 0.02 mm | |||
| Lateral runout of brake disc (max.) | Measured value | 0.03 mm | |||
| Lateral runout of wheel hub (max.) | Measured value | 0.03 mm | |||
| Lateral runout of brake disc when installed (max.) | Measured value | 0.06 mm | |||
| Push rod play | Measured at brake pedal plate | Measured value | approx. 1 mm | ||
| Diameter of parking-brake drum | Diameter | 180 mm | |||
| Diameter of parking-brake drum, wear limit | Diameter | 181 mm | |||
| Width of parking-brake shoe | Measured value | 25 mm | |||
| Thickness of parking-brake pad | Measured value | 4.5 mm | |||
| Thickness of parking-brake pad, wear limit | Measured value | 2 mm |