Brake Disc Run-Out Check And Correction

WARNING: This page is about a different variant/trim than selected.

CAUTION: Take care not to contact the parts or tools to the caliper because the paint of caliper will be scratched. And if there is brake fluid on the caliper, wipe it off quickly.

Remove the brake assembly, and then hold it with wire.
Temporarily install the disc with the hub nut.
Place a dial gauge approximately 5 mm from the outer circumference of the brake disc, and measure the run-out of the disc.
Limit: 0.03 mm (0.0012 inch)

Fig 1: Measuring Run-out Of Disc
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
If the brake disc run-out exceeds the limit, correct it as follows:
1. Chalk phase marks on the wheel stud and the brake disc, which run-out is excessive as shown.
  
  Fig 2: Locating Chalk Marks On Wheel Stud
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. Remove the brake disc. Then place a dial gauge as shown, and measure the end play by pushing and pulling the wheel hub.
  Limit: 0.05 mm (0.002 inch)
3. If the end play exceeds the limit, disassemble the hub and knuckle assembly to check each part.
4. If the end play does not exceed the limit, dephase the brake disc and secure it. Then recheck the brake disc run-out.
  
  Fig 3: Checking Wheel Bearings For End Play
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  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.
    
    Fig 4: Measuring Wheel Bearings End Play (Rear)
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  - When the on-the-car type lathe is used, first install a 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 N. m (74 ft-lb). 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.
If the run-out cannot be corrected by changing the phase of the brake disc, replace the brake disc or grind it with the on-the-car type brake lathe ("Accuturn-8750" or equivalent).

Fig 5: Identifying M12 Flat Washer
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.