When brake disc machining is required, Hyundai recommends the use of an on-car brake lathe, PFM 9.0 or higher version made by PRO-CUT. The SPX part number is 38-PFM90.5 for PFM 9.0 brake lathe with five adapters. The tool is also available through the Hyundai Dealer Equipment Program at (866) 539-4248.
When measuring the brake disc for minimum service thickness and runout, be sure to remove all surface contamination and corrosion.
Measure the disc thickness at 8 points (every 45 degrees). Measure at the same distance (5 mm/0.2 inch) inboard of the disc outer edge. Record these measurements on the repair order. Measure the rotor thickness before and after machining to ensure that the disc is within specification.
After machining, with the rotor fully mounted, inspect disc runout by mounting a dial indicator so that it touches the disc about 5 mm/0.2 inch inboard from the outer edge. Record the runout measurement and refer to the applicable shop manual for runout tolerance.
NOTE: When reinstalling the wheel, tighten the wheel fasteners in a star pattern to avoid distorting the disc.