Brake Rotor/Disc: Testing and Inspection
DISC BRAKE ROTOR CHECKCAUTION: Disc brakes must be kept within the allowable service values in order to maintain normal brake operation.
Before turning the brake disc, the following conditions should be checked.
FRONT BRAKE DISC RUN-OUT CHECK AND CORRECTION
1. Remove the caliper support; then raise the caliper assembly upward and secure it with a wire.
2. Inspect the disc surface for grooves, cracks and rust. Clean the disc thoroughly and remove all rust.
3. Place a dial gauge approximately 5 mm (0.2 inch) from the outer circumference of the brake disc, and measure the runout of the disc.
Limit: 0.06 mm (0.002 inch)
CAUTION:
^ After a new brake disc is installed, always grind the brake disc with on-the-car type brake lathe. If this step is not carried out, the brake disc run-out exceeds the specified value, resulting in judder.
^ When the on-the-car type lathe is used, first install M12 flat washer on the stud bolt in the brake disc side according to the figure, and then install the adapter. If the adapter is installed with M12 flat washer not seated, the brake disc rotor may be deformed, resulting in inaccurate grinding.
^ Grind the brake disc with all wheel nuts diagonally and equally tightened to the specified torque 100 Nm (74 ft. lbs.). When all numbers of wheel nuts are not used, or the tightening torque is excessive or not equal, the brake disc rotor or drum may be deformed, resulting in judder.
4. If the run-out of the brake disc is limit value or more, turn rotor with an on-car type brake lathe ("Accuturn-8750" or equivalent) If it still exceeds the limit, inspect hub end play.
Limit: 0.05 mm (0.002 inch)
5. If the play exceeds the limit, check the hub. If the play does not exceed the limit, replace the brake disc.
REAR BRAKE DISC RUN-OUT CHECK AND CORRECTION
1. Remove the caliper support; then raise the caliper assembly upward and secure it with a wire.
2. Check the disc surface for grooves, cracks and rust Clean the disc thoroughly and remove all rust.
3. Place a dial gauge approximately 5 mm (0.2 inch) from the outer circumference of the brake disc, and measure the runout of the disc.
Limit: 0.08 mm (0.003 inch)
4. If the run-out of the brake disc is the limit value or more, change the phase of the disc and hub, and then measure the runout again.
1. Before removing the brake disc, place a mating mark on both the wheel stud and disc with chalk where the runout is greatest.
2. Place a dial gauge as shown in the illustration, and then move the hub in the axial direction and measure the play.
Limit: 0.05 mm (0.002 inch)
3. If the play does not exceed the limit install the brake disc at a different phase, and then check the runout of the brake disc again.
5. If the runout cannot be corrected by changing the phase of the brake disc, replace the disc.
BRAKE DISC THICKNESS CHECK
1. Remove dirt and rust from the brake disc surface
2. Using a micrometer, measure disc thickness at eight positions, approximately 45 degrees apart and 10 mm (0.4 inch) in from the outer edge of the disc
<2.4L ENGINE>
Standard value: 24.0 mm (0.9 inch)
Minimum limit: 22.4 mm (0.88 inch)
<3.0L ENGINE>
Standard value: 26.0 mm (1.02 inch)
Minimum limit: 24.4 mm (0.96 inch)
NOTE: Thickness variation (at least 8 positions) should not be more than 0.015 mm (0.0006 inch).
CAUTION:
^ After a new brake disc is installed, always grind the brake disc with on-the-car type brake lathe. If this step is not carried out, the brake disc run-out exceeds the specified value, resulting in judder.
^ When the on-the-car type lathe is used, first install M12 flat washer on the stud bolt in the brake disc side according to the figure, and then install the adapter. If the adapter is installed with M12 flat washer not seated, the brake disc rotor may be deformed, resulting in inaccurate grinding.
^ Grind the brake disc with all wheel nuts diagonally and equally tightened to the specified torque 100 Nm (74 ft. lbs.). When all numbers of wheel nuts are not used, or the tightening torque is excessive or not equal, the brake disc rotor or drum may be deformed, resulting in judder.
3. If the disc thickness is less than the limits, replace it with a new one. If thickness variation exceeds the specification, turn rotor with an on-the-car type brake lathe ("Accuturn-8750" or equivalent).
If the calculated final thickness after turning the rotor is less than the standard value, replace the disc.
1. Remove dirt and rust from the brake disc surface.
2. Measure the disc thickness at four positions or more.
Standard value: 10.0 mm (0.4 inch)
Minimum limit: 8.4 mm (0.33 inch)
NOTE: Thickness variation (at least 8 positions) should not be more than 0.015 mm (0.0006 inch).
CAUTION:
^ After a new brake disc is installed, always grind the brake disc with on-the-car type brake lathe. If this step is not carried out, the brake disc runabout exceeds the specified value, resulting in judder.
^ When the on-the-car type lathe is used, first install M12 flat washer on the stud bolt in the brake disc side according to the figure, and then install the adapter. If the adapter is installed with M12 flat washer not seated, the brake disc rotor may be deformed, resulting in inaccurate grinding.
^ Grind the brake disc with all wheel nub diagonally and equally tightened to the specified torque 100 Nm (74 ft. lbs.). When all numbers of wheel nub are not used, or the tightening torque is excessive or not equal, the brake disc rotor or drum may be deformed, resulting in judder.
3. If the disc is less than 8.4 mm (0.33 inch) thick, replace it with a new one if thickness variation exceeds the specification, turn rotor with an on-the-car brake lathe ("Accuturn-8750" or equivalent). If the calculated final thickness is less than the standard value, replace the disc.
BRAKE DISC INSIDE DIAMETER CHECK
1. Remove the rear brake assembly, raise the rear brake assembly and secure it with a wire, etc.
2. Remove the brake disc.
3. Measure the inside diameter of the hub and disc at two or more locations.
Standard value: 168.0 mm (6.61 inches)
Limit: 169.0 mm (6.65 inches)
4. Replace the brake discs and shoe and lining assembly when the wear exceeds the limit value or if the measured areas are not equal to each other. (concentric).