Brake Rotor Assembled Lateral Runout Measurement
Brake Rotor Assembled Lateral Runout Measurement
Special Tools
J-45101 - Hub and Wheel Runout Gauge
Warning: Refer to Brake Dust Warning (Brake Dust Warning).
Note:
* Brake rotor assembled lateral runout (LRO) exceeding the maximum allowable specification can cause thickness variation to develop in the brake rotor over time, usually between 4 800-11 300 km (3,000-7,000 mi).
* Brake rotor thickness variation MUST be checked BEFORE checking for assembled lateral runout (LRO). Thickness variation exceeding the maximum acceptable level can cause brake pulsation. Refer to Brake Rotor Thickness Variation Measurement (Brake Rotor Thickness Variation Measurement).
1. If the brake rotor has been REFINISHED or REPLACED with a new rotor, proceed to step 7.
2. If the brake rotor meets the following criteria, proceed to step 3.
* The rotor is within specifications and is being REUSED.
* The rotor has NOT been refinished.
* The rotor does NOT exhibit thickness variation exceeding the maximum allowable level.
3. Mount a dial indicator, J-45101 - Hub and Wheel Runout Gauge, or equivalent, to the steering knuckle and position the indicator button so it contacts the brake rotor friction surface at a 90 degree angle, approximately 13 mm (0.5 in) from the outer edge of the rotor.
4. Measure and record the assembled LRO of the brake rotor.
1. Rotate the rotor until the lowest reading is displayed on the indicator dial, then set the dial to zero.
2. Rotate the rotor until the highest reading is displayed on the dial.
3. Mark the location of the high spot relative to the nearest wheel stud, or studs.
4. Measure and record the amount of LRO.
5. Compare the brake rotor assembled LRO to the following specification:
Front brake rotor maximum allowable assembled lateral runout: 0.05 mm (0.002 in)
6. If the brake rotor assembled LRO exceeds the specification, refinish the rotor to ensure true parallelism. Refer to Brake Rotor Refinishing (Procedures). After refinishing the rotor, proceed to step 14.
7. Mount a dial indicator, J-45101 - Hub and Wheel Runout Gauge, or equivalent, to the steering knuckle and position the indicator button so it contacts the brake rotor friction surface at a 90 degree angle, approximately 13 mm (0.5 in) from the outer edge of the rotor.
8. Measure and record the assembled LRO of the brake rotor.
1. Rotate the rotor until the lowest reading is displayed on the indicator dial, then set the dial to zero.
2. Rotate the rotor until the highest reading is displayed on the dial.
3. Mark the location of the high spot relative to the nearest wheel stud, or studs.
4. Measure and record the amount of LRO.
9. Compare the brake rotor assembled LRO to the following specification:
Front brake rotor maximum allowable assembled lateral runout: 0.05 mm (0.002 in)
10. If the brake rotor assembled LRO measurement exceeds the specification, bring the LRO to within specifications. Refer to Brake Rotor Assembled Lateral Runout Correction (Brake Rotor Assembled Lateral Runout Correction).