Tools You Will Likely Need:
* Jack and jack stands: Essential for safe vehicle lifting.
* Wheel chocks: To prevent the vehicle from rolling.
* Lug wrench: To remove the wheel.
* Socket set and wrenches: Various sizes, likely including metric.
* Hammer and punch: For removing and installing components.
* Bearing packing grease: Specific type for wheel bearings.
* New wheel bearings: Buy the correct part number for your specific vehicle. Consider buying a complete hub assembly to simplify the process.
* Torque wrench: Crucial for tightening components to the correct specification.
* Pry bar: Might be needed to separate components.
* Clean rags: To keep things clean.
* Penetrating oil (PB Blaster, etc.): To loosen seized bolts.
* Shop manual: Highly recommended.
General Steps (Consult your repair manual for precise details):
1. Safety First: Park on a level surface, engage the parking brake, and use wheel chocks. Raise the vehicle safely using a jack and secure it with jack stands.
2. Remove the Wheel: Remove the lug nuts and take off the wheel.
3. Remove the Brake Caliper: Remove the caliper bolts and carefully hang the caliper out of the way using a wire or bungee cord. Do not let the brake hose hang freely; support it to prevent damage.
4. Remove the Rotor (Disc Brake): Remove the rotor retaining bolts or screws (depending on your model). Some rotors might slide off after removing the caliper; others might require a puller.
5. Remove the Axle Nut: This is usually very tight; use a breaker bar and penetrating oil if necessary. Support the hub assembly to prevent it from falling.
6. Remove the Hub Assembly (or individual bearing components): This is where things get more complex and vary depending on your specific year and model. You might need to remove cotter pins, snap rings, and other components. Your repair manual will guide you through this. Often, removing the hub assembly as a whole is the simplest option.
7. Inspect and Replace the Bearing(s): Carefully inspect the old bearing for damage. If you're replacing individual bearings, note their orientation for proper reinstallation.
8. Pack New Bearings with Grease: Pack the new bearings thoroughly with the correct type of wheel bearing grease.
9. Reinstall Components: Reassemble everything in the reverse order of removal, paying close attention to the order and torque specifications for each bolt and nut (refer to the repair manual).
10. Torque Specifications: Tighten all bolts and nuts to the manufacturer's specified torque values using a torque wrench. This is critical to prevent damage and ensure safety.
11. Reinstall the Wheel and Lower the Vehicle: Carefully reinstall the wheel and lower the vehicle.
12. Test Drive: Test drive the vehicle to ensure everything is working correctly and there are no unusual noises.
Important Considerations:
* Hub Assembly vs. Individual Bearings: Replacing the entire hub assembly is often easier and less prone to error than replacing individual bearings.
* Torque Specifications: Incorrect torque can lead to premature failure or catastrophic damage. Use a torque wrench.
* Repair Manual: A repair manual specific to your 1999 GMC Jimmy is essential for this job.
* Professional Help: If you are not comfortable performing this repair yourself, it's best to take your vehicle to a qualified mechanic.
This is a simplified overview. Always refer to your vehicle's repair manual for detailed instructions and torque specifications. Failure to do so could result in damage to your vehicle or personal injury.
