1. Preparation:
* Safety First: Disconnect the negative battery terminal. Use jack stands to securely lift the vehicle. Wear safety glasses and gloves.
* Gather Tools and Parts: You'll need a jack, jack stands, wheel chocks, torque wrench, socket set (metric), various wrenches (including possibly a large pipe wrench for stubborn nuts), a ball joint separator, a hammer, a punch, a press (or a socket and hammer for pressing out the bearings – less ideal), a grease gun, new wheel bearings (make sure to get the correct ones for your specific Blazer), new seals, and possibly a new ABS sensor ring (if damaged during removal). A service manual specific to your year and model Blazer is highly recommended.
* Gather Information: Consult a repair manual (Haynes, Chilton, or a factory service manual) for detailed instructions, torque specifications, and diagrams specific to your vehicle. These manuals provide crucial step-by-step guidance and torque values crucial to success.
2. Disassembly:
* Remove the Wheel and Tire: Loosen the lug nuts before lifting the vehicle, then remove the wheel.
* Remove the Brake Caliper: Carefully remove the brake caliper and support it to prevent it from hanging by the brake line. You might need to use a C-clamp or a wire to hold it out of the way.
* Remove the Rotor: Depending on the rotor design, you might need to remove some retaining bolts or use a puller.
* Disconnect the ABS Sensor (if applicable): Carefully disconnect the ABS sensor wire harness from the sensor, taking care not to damage the wire.
* Remove the Cotter Pin and Castle Nut: Remove the cotter pin securing the castle nut on the axle shaft. This nut is usually very tight.
* Remove the Axle Nut: Use a socket and breaker bar (or an impact wrench if you have one) to remove the axle nut. This will require significant force.
* Separate the Ball Joint: Use a ball joint separator to separate the lower ball joint from the steering knuckle.
* Remove the Hub Assembly: Once the ball joint is separated, the hub assembly should come off. This may require some gentle persuasion with a hammer and punch. Be careful not to damage any components.
3. Bearing Replacement:
* Remove the Old Bearings and Seals: This usually involves using a press to remove the old bearings from the hub assembly. Using a socket and hammer is less precise and can damage the hub. A shop press makes this much easier. The seals will likely need to be replaced as well.
* Install the New Bearings and Seals: Carefully press the new bearings and seals into place. Proper seating is crucial. Again, a shop press is highly recommended for this step.
* Clean and Inspect Components: Thoroughly clean all the components before reassembly to remove old grease and debris.
4. Reassembly:
* Reverse the Disassembly Process: Carefully reassemble everything in the reverse order of disassembly, paying close attention to proper alignment and torque specifications.
* Torque Specifications: Use a torque wrench to tighten all bolts and nuts to the manufacturer's specifications found in your repair manual. This is incredibly important to prevent premature failure or damage.
* Pack with Grease: Pack the new bearings with fresh grease using a grease gun.
* Bleed the Brakes (if necessary): If you had to open the brake system, you'll likely need to bleed the brakes to remove any air that may have entered the system.
Important Considerations:
* Press: Having access to a press, either a shop press or a hydraulic press, will greatly simplify the process of removing and installing the bearings. Attempting to remove and install the bearings with only a hammer and socket can result in damage to the bearings or the hub assembly.
* ABS Sensor: Be extremely careful with the ABS sensor. If damaged, it will need to be replaced.
* Torque Specifications: Incorrect torque values will result in premature component failure or damage.
* Professional Help: If you are not comfortable with this level of automotive repair, it's strongly recommended to take your vehicle to a qualified mechanic.
This is a general overview. Always consult a repair manual specific to your vehicle for detailed instructions and torque specifications before attempting this repair. Improperly performed, this repair can lead to serious safety issues.
