Toyota 43512-42040 Front 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 against the hub flange; if the lug nuts don't contact the disc when screwed on all the way, install washers under them. Remove the brake caliper without disconnecting the brake hose, suspending it out of the way with a piece of wire to avoid stretching or pinching the flexible brake hose. Detach the mounting bracket by removing the two bolts while being careful not to lose the pad support plates. Visually inspect the disc surface for score marks and other damage; light scratches and shallow grooves are normal, but deep scoring requires disc removal and refinishing. Check both sides of the disc, as severe wear may necessitate replacement. To check disc runout, place a dial indicator about 1/2-inch from the outer edge of the disc, set it to zero, and turn the disc, ensuring the reading does not exceed the allowable run-out limit; resurfacing is recommended regardless of the reading to ensure a smooth finish. The disc must not be machined to a thickness under the specified minimum, which is typically cast or stamped into the inside of the disc, and can be checked with a micrometer. Remove the lug nuts holding the disc in place and slide the disc off the hub; if removing a rear disc that won't come off, it may be interfering with the parking brake shoes, requiring the removal of a plug and adjustment of the parking brake shoes. Place the new disc in position over the threaded studs, install the mounting bracket and caliper while tightening the bolts, then install the wheel and lower the vehicle to the ground, tightening the lug nuts. Depress the brake pedal a few times to bring the brake pads into contact with the disc, and check the operation of the brakes carefully before driving the vehicle.