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Brake Disc Assembled Lateral Runout Measurement

Special Tools

For equivalent regional tools, refer to Special Tools .

Warning: Refer to Brake Dust Warning in the Preface section.

Note: 

1. Matchmark the position of the brake disc to the wheel studs if this has not been done already.

Note: Whenever the brake disc has been separated from the hub/axle flange, any rust or contaminants should be cleaned from the hub/axle flange and the brake disc mating surfaces. Failure to do this may result in excessive assembled lateral runout (LRO) of the brake disc, which could lead to brake pulsation.

2. Inspect the mating surface of the hub/axle flange and the brake disc to ensure that there are no foreign particles, corrosion, rust, or debris remaining. If the wheel hub/axle flange and/or if the brake disc mating surfaces exhibit these conditions, perform the following steps:

2.1.	Remove the brake disc from the vehicle. Refer to Front Brake Disc Replacement and/or Rear Brake Disc Replacement .

2.2.	Using the CH-42450-A wheel hub resurfacing kit, thoroughly clean any rust or corrosion from the mating surface of the hub/axle flange.

2.3.	Using the CH-41013 disc resurfacing kit, thoroughly clean any rust or corrosion from the mating surface of the brake disc.

2.4.	Clean the friction surfaces of the brake disc with methylated spirit, or an equivalent approved brake cleaner.

3. Install the disc to the hub/axle flange using the matchmark made prior to removal.



4. Hold the disc firmly in place against the hub/axle flange and install one of th CH-45101-100 conical brake disc washers (1), and one lug nut (2) onto the upper-most wheel stud.
5. Continue to hold the disc secure and tighten the wheel nut firmly by hand.



6. Install the remaining CH-45101-100 conical brake disc washers and lug nuts onto the wheel studs and tighten the nuts firmly by hand in a star-pattern.
7. Tighten the lug nuts in a star-pattern to specification. Refer to Tyre and Wheel Removal and Installation .
8. If the brake disc has been REFINISHED or REPLACED with a new disc, proceed to step 14.
9. If the brake disc meets the following criteria, proceed to step 10.

•	The disc is within specifications and is being REUSED.

•	The disc has NOT been refinished.

•	The disc does NOT exhibit thickness variation exceeding the maximum allowable level.




10. Mount a dial indicator, CH-45101 hub and wheel runout gauge, or equivalent, to the steering knuckle and position the indicator button so it contacts the brake disc friction surface at a 90 degree angle, approximately 13 mm (0.5 in) from the outer edge of the disc.
11. Measure and record the assembled LRO of the brake disc.

11.1.

Rotate the disc until the lowest reading is displayed on the indicator dial, then set the dial to zero.

11.2.

Rotate the disc until the highest reading is displayed on the dial.

11.3.

Mark the location of the high spot relative to the nearest wheel stud, or studs.

11.4.

Measure and record the amount of LRO.

12. Compare the brake disc assembled LRO to the following specification:

Specification

•	Front brake disc maximum allowable assembled lateral runout: 0.05 mm (0.002 in)

•	Rear brake disc maximum allowable assembled lateral runout: 0.05 mm (0.002 in)

13. If the brake disc assembled LRO is within specifications, proceed to step 18.

If the brake disc assembled LRO exceeds the specification, refinish the disc to ensure true parallelism. Refer to Brake Disc Refinishing . After refinishing the disc, proceed to step 14.

14. Mount a dial indicator, CH-45101 hub and wheel runout gauge, or equivalent, to the steering knuckle and position the indicator button so it contacts the brake disc friction surface at a 90 degree angle, approximately 13 mm (0.5 in) from the outer edge of the disc.
15. Measure and record the assembled LRO of the brake disc.

15.1.

Rotate the disc until the lowest reading is displayed on the indicator dial, then set the dial to zero.

15.2.

Rotate the disc until the highest reading is displayed on the dial.

15.3.

Mark the location of the high spot relative to the nearest wheel stud, or studs.

15.4.

Measure and record the amount of LRO.

16. Compare the brake disc assembled LRO to the following specification:

Specification

•	Front brake disc maximum allowable assembled lateral runout: 0.05 mm (0.002 in)

•	Rear brake disc maximum allowable assembled lateral runout: 0.05 mm (0.002 in)

17. If the brake disc assembled LRO measurement exceeds the specification, bring the LRO to within specifications. Refer to Brake Disc Assembled Lateral Runout Correction .
18. If the brake disc assembled LRO measurement is within specification, install the brake calliper and depress the brake pedal several times to secure the disc in place before removing the CH-45101-100 conical brake disc washers and the lug nuts.