Tools You'll Need:
* Jack and jack stands: Essential for safety. Never work under a vehicle supported only by a jack.
* Wheel chocks: To secure the other wheels.
* Lug wrench: To remove the wheel.
* Impact wrench (highly recommended): Makes the job significantly easier, especially for removing the hub nut. A breaker bar and a lot of muscle can substitute, but it's much harder.
* Socket set: Various sizes, including one that fits the hub nut.
* Ball joint separator: To separate the ball joint from the control arm.
* Tie rod end separator: To separate the tie rod end from the steering knuckle.
* C-clamp or bearing puller: To remove the old bearing. A specific wheel bearing puller is ideal.
* Press (recommended): For installing the new bearing. While you *can* sometimes tap it in carefully, a press ensures proper seating and prevents damage.
* New wheel bearing: Make sure you get the correct one for your vehicle. The bearing's part number is crucial.
* Penetrating oil (like PB Blaster): To loosen seized bolts and nuts.
* Torque wrench: Absolutely necessary for tightening bolts to the correct specifications. Incorrect torque can damage components.
* Hammer and punches (optional but helpful): For carefully removing and installing components if a press isn't available.
* Gloves and safety glasses: Protect yourself.
Steps (General Outline):
1. Safety First: Secure the vehicle with jack stands and wheel chocks. Disconnect the negative battery terminal.
2. Remove the Wheel: Remove the lug nuts and wheel.
3. Disconnect Brake Caliper: Use a suitable wrench or socket to remove the caliper mounting bolts. Hang the caliper using wire or a bungee cord to keep it out of the way. Do not let the brake line hang freely; it could damage the line.
4. Disconnect ABS Sensor (if applicable): Some models have an ABS sensor attached to the knuckle. Carefully unplug it.
5. Disconnect Tie Rod End: Use a tie rod end separator to separate the tie rod end from the steering knuckle. You'll likely need to loosen the jam nut first.
6. Disconnect Ball Joint: Use a ball joint separator to separate the ball joint from the control arm.
7. Remove the Hub Nut: This is usually a very large nut. An impact wrench is highly recommended here. Penetrating oil may be necessary.
8. Remove the Rotor (if necessary): Depending on your vehicle, the rotor might need to come off before you can access the bearing.
9. Remove the Old Bearing: This is where a bearing puller or press is essential. Carefully remove the old bearing, paying attention to how it comes apart. The inner and outer races might be separate.
10. Install the New Bearing: Using a press is highly recommended. If you're using a press, ensure the bearing is properly seated. If tapping in, do so carefully and evenly to avoid damage.
11. Reassemble: Reinstall the components in reverse order, paying close attention to the torque specifications in your repair manual for all fasteners. This includes the hub nut, which needs to be tightened correctly.
12. Check for Correct Operation: After reassembly, check for proper steering and braking function. Test drive the vehicle carefully.
Important Considerations:
* Repair Manual: A repair manual specific to your 2002 Mercury Mountaineer is invaluable. It will provide detailed instructions, torque specifications, and diagrams.
* Parts: Ensure you get the correct wheel bearing for your vehicle. The wrong bearing will not work.
* Press: A press makes this job much easier and less likely to damage the new bearing.
* Safety: Working on your vehicle can be dangerous. Always prioritize safety.
This is a complex repair. If you're not comfortable performing this task, it's best to take your vehicle to a qualified mechanic. Improperly installed bearings can lead to serious safety issues.
