You can replace your own brake rotors on your Chevy Blazer provided you have the proper tools. This can save you a great deal of money on labor charges from your local service station. Allow about 30 to 60 minutes per side in order to take off the old ones and replace them with new ones.
Park the Blazer on a flat, level surface. Turn the steering wheel all the way to the right in order to work on the left front wheel and reverse procedure for the right side. Place the Blazer in park and shut the key off.
Place a wheel chock behind one or both rear tires. Using the 1/2 inch drive breaking bar and appropriate sized deep socket, crack the lug nuts loose. Lift the vehicle with a floor jack and place a jack stand under the bottom control arm below the shock absorber.
Squeeze the piston of the caliper in by placing the large screwdriver or medium angle pry bar in between the rotor and the caliper. Do this slowly until the caliper has movement on the slides. Squeeze it in as far as you can.
Remove caliper bolts using 3/8 inch socket and 3/8 inch hex head socket or 3/8 inch Allen wrench. Place caliper up on top of upper control arm and rest on upper ball joint.
Remove caliper bridge bolts using the breaking bar and appropriate sized 1/2 inch drive socket.
Remove the old rotor. If this does not come loose on the hub, you may have to hammer the rotor off, being careful not to hit the fender well. Hit the exposed area of the rotor from behind and in front.
Clean the hub as best you can with a medium grade sandpaper. Try to clean most of any present rust along the edge of the hub and on the face of the hub by lug studs.
Clean the new rotor with canned brake clean and a shop rag to remove rust preventive coating. Be liberal and clean thoroughly.
Place the new rotor on the hub. Replace the caliper bridge and tighten as tight as you can with the breaking bar.
Replace the caliper over the rotor and be sure you do not twist the brake hose incorrectly. If the caliper does not go on, you may need to remove the pads and squeeze the piston in further with a C-clamp or a large pair of channel locks. Do not force it on if it does not fit easily. Tighten.
Replace the tire and tighten lug nuts as tight as you can get them with the wheel raised. Remove the jack stand and lower vehicle and torque the lug nuts to 100 foot pounds in an alternate sequence.
Repeat this procedure for the other side.
Pump up the brake pedal to restore hydraulic pressure to the caliper pistons. Remove the wheel chock and test drive the car.
