Prepare the TrailBlazer

• 1). Place chocks around the wheels not to be serviced. If you are working on the front brakes, engage the TrailBlazer's parking brake. Loosen the lug nuts on the wheels to be serviced. Jack the vehicle to raise the wheel from the ground. Brace with jack stands, for safety.
  
  
• 2). Remove the lug nuts and remove the wheel.
  
  
• 3). Unbolt the upper and lower caliper bolts and set aside. You will use the torx head socket set to loosen and remove the bolts. Slide the caliper off the rotor and suspend the caliper with a coat hanger to keep any strain off the brake line. You can attach the caliper to any solid metal surface behind the rotor assembly, such as the springs.
  
  
• 4). Locate the retaining screw securing the rotor to the hub. This screw, if your vehicle's model year is equipped, is found between two of the lug posts on the rotor. The screw will require a torx head screwdriver or socket. Remove and set aside.
  
  
• 5). Grasp the rotor with both hands and pull directly away from the hub. The rotor should slide freely off the hub. If the rotor is corroded to the hub, spray a penetrating lubricant -- such as WD-40 -- into the crack between the rotor and hub and around the base of the lug nuts. Allow the penetrating lubricant to loosen the corrosion and re-attempt. You may strike the rotor with a rubber mallet to loosen, as well.
  
  

Change the Rotor

• 1). Spray the new or resurfaced rotor with brake parts cleaner until all oils or debris are removed. Spray the hub and interior of the wheel well to ensure the rotor seats flush against both the hub and wheel well. A non-flush seat will result in the rotor being positioned in a slant with relation to the brake caliper. Mis-aligned rotors will wear unevenly, causing pulsing or throbbing in the brakes.
  
  
• 2). Install the rotor by sliding it over the lug posts and pressing it flush against the hub. Insert the retaining screw and tighten, if equipped.
  
  
• 3). Slide the caliper over the rotor. If the rotor has been resurfaced, the caliper should slide over the rotor. If the rotor is new -- with a greater thickness than the old -- the caliper will require compression. To compress the caliper, open the bleed line at the top of the caliper and compress the brake shoe against the caliper housing. The compression will cause brake fluid to leak from the bleed screw. Catch the brake fluid with a rag or container and discard. Re-tighten the brake bleed screw. Align the caliper over the rotor and slide on.
  
  
• 4). Insert and tighten the upper and lower caliper bolts to secure the caliper in place over the rotor.
  
  
• 5). Install the wheel over the lug posts and tighten the lug nuts in a star pattern to evenly distribute the tension on the rotor and hub.
  
  
• 6). Remove the jack stands and lower the vehicle. Re-tighten the lug nuts. Remove the parking brake and chocks. Re-tighten the lug nuts after 50 to 100 miles of driving.