The brake pads in your Lexus RX300 work in conjunction with the rotor, master cylinder, caliper and piston to slow and stop the vehicle every time you push on the brake pedal. After so many cycles of rubbing against the rotor, however, the pads wear down. For this reason, Lexus recommends checking the brake pads every 15,000 miles. You can help your Lexus brake system work at its best by replacing the worn pads at home, using a few common tools right out of your toolbox.
Remove about two-thirds of the brake fluid from the reservoir on the brake master cylinder with a hand-siphon pump. Store the brake fluid in a sealable container for later recycling.
Loosen but do not remove the lug nuts on both front or rear wheel assemblies, depending on which set of pads you are replacing. Use a lug wrench.
Raise the front or rear of your Lexus, using a floor jack and support it on two safety stands.
Take off both wheel assemblies.
Put a large C-clamp over the top of the brake caliper and slowly press against the outer brake pad with the clamp screw to seat the caliper piston back into its bore. Remove the C-clamp.
Unfasten and remove the lower caliper mounting bolt with a ratchet and six-point socket.
Swing the caliper away from the caliper bracket. Hold it in place with a piece of wire, if necessary.
Make a note of the type and position of the two sets of shims located on the outer side of each brake pad and the two metal clips on the lower and upper side of the caliper bracket. Some of these shims have an arrow to indicate the proper mounting position. Remove the shims and brake pads.
Clean the brake assembly with brake parts cleaner and a lint-free rag to remove pad-friction dust if necessary.
Position the new set of brake pads on the caliper bracket. Before installing the new shims and clips, coat both sides of each shim that seats next to the inner and outer brake pads with brake grease and replace the hardware.
Swing the caliper back into position and tighten the mounting bolt with a torque wrench to 25 foot-pounds on the front calipers and 14 foot-pounds on the rear calipers.
Replace the brake pads on the opposite wheel assembly.
Mount the wheel assembly and secure them with the lug nuts.
Lower your Lexus and tighten the lug nuts with the lug wrench.
Refill the reservoir on the brake master cylinder with new brake fluid to the "Max" mark and replace the reservoir cap. Slowly pump the brake pedal until it becomes firm. Check the brake fluid level and add more if necessary.
