1990 Toyota 4Runner Replace Rotors
The 1990 Toyota 4Runner SUV is manufactured with front disk brakes, and has been for the entire model run. These disk brakes use rotors and pads to apply friction and stop the vehicle. The hydraulically actuated caliper presses the pads against the rotor surface, and this surface can wear thin and require replacement. It takes approximately 40 minutes to replace the rotor in a 4Runner.
- Lift the 4Runner at the front wheel by placing the jack head underneath the frame rail (just behind the wheel), then pumping the lever until the wheel is in the air. Do not place the jack onto the body or suspension due to possible damage. Place a jack stand on the same frame rail near the jack for extra support. Take the wheel off by turning the lug nuts counterclockwise and pulling the wheel from the hub. Store the wheel away from the work area.
- Remove the caliper by turning the rear mount bolts counterclockwise. The caliper will slide off of the rotor, and should be placed on the top of the control arm or tied to it with zip ties; the caliper's brake lines can be damaged by allowing the caliper to dangle. Remove the pads by gently prying their clips out with the screwdriver, then pulling the pads from the caliper pistons.
- Remove the rotor by turning the spindle nut counterclockwise, and pulling the rotor free of the hub. The wheel bearings can be checked at this time for damage or a lack of lubricant. Replace the rotor by pressing the new unit over the axle and securing the spindle nut by hand. Once the nut is threaded, use the wrench to tighten it completely.
- Replace the pads onto the caliper pistons and secure their clips, if applicable. Slide the caliper back over the rotor and secure the rear mount bolts in a clockwise direction.
- Replace the wheel and tighten the lug nuts clockwise, in an alternating pattern. Lower the 4Runner from the jack, after removing the jack stand. Repeat the entire procedure on the opposite front brake.
Tips & Warnings
- Replace the pads when replacing the rotor, so they will mate correctly.
- It is recommended to purge the brake system with fresh fluid after making major repairs to the braking system.
- Use extreme caution when working underneath a lifted truck.