Toyota 42431-12310 Rear Disc

Loosen the wheel lug nuts, raise the vehicle, and support it securely on jackstands. Remove the wheel and install the lug nuts to hold the disc in place. Remove the brake caliper without disconnecting the brake hose, suspending it out of the way with a piece of wire to avoid strain on the hose, and ensure the upper slide pin boot remains undistorted. Detach the caliper mounting bracket by removing its bolts. Visually inspect the disc surface for score marks and damage; while light scratches and shallow grooves are normal, deep scoring necessitates disc removal and refinishing. Check both sides of the disc, noting that severe wear from neglected brake pads requires replacement. To assess disc runout, position a dial indicator about 1/2-inch from the outer edge, set it to zero, and turn the disc, ensuring the reading does not exceed the allowable limit; if it does, refinishing is required. Regardless of the reading, resurfacing is recommended for a smooth finish to prevent brake pedal pulsation. If not resurfacing, remove any glaze with sandpaper or emery cloth using a swirling motion. Ensure the disc is not machined below the minimum allowable refinish thickness, which can be checked with a micrometer. Make match marks on the disc and a wheel stud for proper reinstallation, then remove the lug nuts and slide the disc from the hub. Position the new disc over the threaded studs, install the caliper mounting bracket and tighten the bolts to the specified torque, followed by the caliper, also tightening its bolts to the specified torque without needing to bleed the system. Finally, install the wheel and lug nuts, lower the vehicle, tighten the lug nuts, and depress the brake pedal a few times to engage the brake pads with the disc, checking the brakes' operation carefully before driving.