Attention:
- Increased axial runout of the brake disc can lead to the development of uneven disc wear during 5000-10000 km of run.
- A brake disc thickness variation check must be done BEFORE checking disc axial runout. Different thickness of the brake disc leads to increased pulsation on the brake pedal.
1. Mark the relative position of the brake disc and wheel studs if not already done.
Attention: every time after removing the brake disc, carefully clean the seat of the disc. Dirt in the seat can cause increased axial runout of the disc.
2. Check up a condition of landing surfaces of a nave and a brake disk. Make sure there is no dirt or food. If the condition of the surfaces is unsatisfactory, perform the following operations:
- A) Remove the brake disc.
- b) With special tools (or their substitutes) clean the seats of the brake disc and hub.
- V) Clean the hub and brake disc with denatured alcohol or an approved brake cleaner.
3. Install the brake disc on the hub using the relative position marks made prior to removal.
4. While holding the brake disc firmly against the hub seat, install the conical washer onto the top stud (1) and conical nut (2).
5. Tighten the cone nut finger tight.
6. Install the remaining studs with the conical washers and nuts as in step 4. Finger tighten the nuts.
7. Using a torque wrench, tighten the nuts to the specified tightening torque according to the diagram "star" (see section "Removal and installation of a wheel").
8. If the dimensions of the brake disc are within the limits allowed by the specification, or the brake disc has been repaired or replaced with a new one.
- A) Attach the dial gauge pole to the steering knuckle. Place the indicator foot on the friction surface of the brake disc, perpendicular to the disc and approximately 13 mm from the outer edge of the disc.
- b) Rotate the dial until you get the minimum reading on the indicator. Set the indicator to zero.
- V) Rotate the dial until you get the maximum indicator reading.
- G) Mark the nearest wheel stud at the point of maximum runout. If the distance to the studs is equal, mark both studs.
- d) Record the amount of beat.
9. If the amount of runout is within acceptable limits, go to step 11. If the runout is more than normal, restore the surface of the brake disc on a lathe and repeat steps 8.
10. If the runout of a new or repaired disc is abnormal, perform runout correction operations, see below "Correction of brake disc runout".
11. If the runout is normal, install the brake caliper and press the brake pedal several times to complete the disc installation.