Rear Brake Disc Runout Check

Place a dial gauge about 5mm (0.2 in.) from the outer circumference of the brake disc, and measure the run-out of the disc.
Brake Disc Run-Out

Limit: 0.05 mm (0.002 in.) or less (new one)

Fig 1: Checking Rear Brake Disc Run-Out
Courtesy of KIA MOTORS AMERICA, INC.
If the runout of the brake disc exceeds the limit specification, replace the disc, and then measure the runout again.
If the runout does not meet the limit specification, remove the disc, turn it 180° and reinstall. Then check the runout of the brake disc again.
If the runout cannot be corrected by changing the position of the brake disc, replace the brake disc.