Grinding Down Parking-Brake Shoes

Information 

• Grinding down applies only to grey cast-iron brakes with one-piece brake discs. 
• Grinding of grey cast-iron brakes on 911 Turbo (991) and 911 GT3 (991) vehicles is not permitted because compound brake discs with aluminum brake disc hubs are installed. 
• Grinding of PCCB brake discs/brake shoes is not permitted. 
• Grinding must be performed after setting the brake shoes to the basic setting. 
• The brake shoes must be grinded down prior to calibration. 
• It is not necessary to grind down the parking-brake shoes when you are removing/installing the brake discs and/or parking-brake shoes. 

Information 

• Each time the brake discs and/or parking-brake shoes (grey cast-iron brakes only) are replaced, the electric parking brake (EPB) must be grinded down after first setting the brake shoes to the basic setting  → 468316 ADJUSTING PARKING-BRAKE SHOES . This does not apply to compound brake discs with aluminum brake disc hubs (911 Turbo and 911 GT3). 
• The electric parking brake will only function fully after it has been grinded down and calibrated. This involves driving the vehicle eight times from standstill to 10 km/h (6 mph) up to max. 20 km/h (12 mph) for a distance of 20 meters. If the distance in meters is not sufficient for several consecutive cycles, you can perform a reset with the vehicle after every cycle and drive on the same stretch of road several times! 
• The >>Grind brake shoes<< routine is initiated using PIWIS Tester II 9818  .

1. Select >>Parking brake<< in the control unit overview. Select >>Maintenance/repairs<< >>Grinding<<. Follow the instructions on PIWIS Tester II.
2. Once the brake shoes have been grinded down correctly, the EPB must be calibrated. → 468316 ADJUSTING PARKING-BRAKE SHOES