Note: The procedure applies equally to both front and rear disc brakes.
Checking the status
1. Loosen the wheel nuts, jack up the car and support it. Remove the wheel in question, then screw the pair of wheel nuts back onto the studs, using 3mm washers underneath to secure the brake disc (if the two disc mounting screws are still in place, there is no need to screw the nuts back on). When checking the rear brake disc, remember to release the parking brake.
2. Remove the brake caliper (see Section Removal and installation of disc brake calipers) and tie it to the side with wire to the suspension element without disconnecting the brake hose.
3. Visually inspect the condition of the disc working surface. Minor defects can be removed using fine-grained sandpaper. To remove grooves deeper than 0.38 mm, the disc should be lapped. Remember that the disc should be inspected from both sides.
4. If pedal pulsation is observed during braking, the lateral runout of the brake disc should be assessed. Attach a plunger-type dial gauge (DTI) approximately 12.7 mm from the outer edge of the disc.
5. Zero the device and start rotating the disk. The measurement result should not go beyond the permissible range specified in the Specifications, otherwise the disk must be given for turning.
Note. The authors of this Manual recommend turning the disks regardless of their condition in order to remove any defects from the working surfaces. In extreme cases, you can limit yourself to processing the disk with fine-grained sandpaper.
6. When turning the disk, special attention should be paid to compliance with the requirements of the Specifications for its minimum permissible thickness. The corresponding marking is provided on the end surface of the disk.
7. The thickness of the disc is measured using a micrometer.
Removal
1. Remove the two bolts securing the caliper anchor bracket to the steering knuckle,
2. or (on the rear wheel brake mechanism) the bolts securing the bracket to the hub assembly. Remove the bracket.
3. Remove the two wheel nuts used to secure the disc to the hub/unscrew the two mounting screws. Remove the disc from the wheel hub.
4. If the disc is "stuck" to the hub, it can be pressed out by screwing a pair of bolts of the appropriate size into the mounting holes. Tighten the bolts evenly and gradually until the disc is completely free. When removing the disc, try not to damage the threads of the wheel mounting studs.
Installation
1. Carefully place the disc on the hub (again, be careful not to damage the wheel studs). Screw in and tighten the mounting screws securely.
2. Install the caliper anchor bracket onto the disc. Tighten the bracket and caliper mounting bolts to the required torque.
3. Replace the wheel, lower the vehicle to the ground and tighten the wheel nuts to the specified torque (see Specifications in Chapter Settings and ongoing maintenance). Press the brake pedal/cock the parking brake lever several times to seat the pads on the disc. If the brake hoses were not disconnected, there is no need to bleed the hydraulic system. Before operating the vehicle, make sure that the brakes are functioning properly.