Here's a general overview of the process. Remember, this is NOT a substitute for a proper repair manual. Variations exist depending on whether you're working on the front or rear, and even between different trim levels.
Tools You'll Likely Need:
* Jack and jack stands: Essential for safety. Never work under a vehicle supported only by a jack.
* Wheel chocks: To prevent the vehicle from rolling.
* Lug wrench: To remove the wheel.
* Socket set and wrenches: Various sizes will be needed.
* Ball joint separator: To separate the ball joint from the steering knuckle (front only).
* Hammer and punch: May be needed for stubborn parts.
* Torque wrench: Absolutely essential for proper tightening of bolts and nuts. Incorrect torque can damage components.
* Wheel bearing press: Highly recommended for proper bearing installation. Improper installation can damage the bearing and hub. A DIY solution using a socket and hammer is risky and may damage parts.
* Penetrating oil: To help loosen rusted or seized bolts.
* Grease: For repacking the new bearing.
* Pry bar: May be needed to separate components.
* Clean rags or shop towels: To keep things clean.
* Safety glasses and gloves: Protect yourself.
General Steps (Front Wheel Bearing - This will vary):
1. Safety First: Secure the vehicle with jack stands, chocks, and the parking brake engaged.
2. Remove the Wheel and Brake Caliper: Remove the wheel. Secure the brake caliper using a wire or bungee cord to keep it out of the way.
3. Disconnect the ABS Sensor (if applicable): Carefully disconnect the ABS sensor wire.
4. Separate Ball Joint: Use a ball joint separator to separate the lower ball joint from the steering knuckle.
5. Remove the Hub and Bearing Assembly: This often involves removing several bolts securing the hub assembly to the knuckle. This is where a repair manual will be invaluable, as the exact method varies by vehicle year and model.
6. Remove the Old Bearing: This is where the wheel bearing press is crucial. Attempting to remove the bearing without one can damage the hub.
7. Install the New Bearing: Use the wheel bearing press to install the new bearing. Ensure it's properly seated.
8. Reassemble: Carefully reassemble all components in the reverse order of removal, paying close attention to torque specifications from your repair manual. This includes properly installing the ABS sensor, tightening the hub assembly, and securing the ball joint.
9. Reinstall Brake Caliper and Wheel: Reinstall the brake caliper, ensuring it's properly seated and the brake pads are not binding. Reinstall the wheel and tighten the lug nuts to the specified torque.
10. Lower the Vehicle: Carefully lower the vehicle from the jack stands.
11. Test Drive: After a short test drive, check for any unusual noises or vibrations.
Rear Wheel Bearing (This will also vary):
The rear wheel bearing replacement process differs from the front. You'll likely need to deal with different components such as the axle flange, and the process may involve removing the axle shaft itself. A repair manual is absolutely essential for this process.
Important Considerations:
* Torque Specifications: Following the correct torque specifications is crucial for proper operation and safety. Improperly tightened components can lead to failure.
* Repair Manual: Again, a repair manual specific to your 2004 GMC Envoy is absolutely necessary. This guide provides only a general overview; specifics will vary.
* Professional Help: If you're not comfortable performing this repair, it's best to take your vehicle to a qualified mechanic. Improperly installed wheel bearings can be extremely dangerous.
This detailed information is for educational purposes only and should not be considered a substitute for professional advice or a repair manual. Always prioritize safety and consult the appropriate resources before attempting this repair.
