Here's a breakdown of how to check the rear wheel bearings:
1. Preparation:
* Safety First: Park on a level surface, engage the parking brake, and use jack stands to securely support the vehicle after lifting it with a jack. Chock the front wheels as an extra precaution.
* Gather Tools: You'll need a jack, jack stands, wheel chocks, a wrench to remove the wheel, and possibly a pry bar (for advanced checks). A mechanic's stethoscope can help isolate noise, but isn't strictly necessary.
2. Visual Inspection:
* Remove the Wheel: Loosen the lug nuts slightly while the wheel is still on the ground, then jack up the vehicle and remove the wheel.
* Inspect the Wheel Hub and Bearing Seal: Look for any obvious damage, leaks (grease or fluid), or signs of rust or corrosion around the wheel hub and the bearing seal. A damaged seal is a strong indicator of a failing bearing.
3. Checking for Play:
* Grab the Wheel: With the wheel removed, firmly grab the wheel hub and try to move it up and down, and side to side. Any noticeable play (movement) indicates a worn bearing. Even slight play is a warning sign.
* Spin the Rotor: Rotate the rotor (the disc attached to the hub) by hand. It should spin smoothly and freely. If it's rough, wobbly, or makes noise, the bearing is likely worn. Listen carefully for any grinding, clicking, humming, or rumbling sounds.
4. Advanced Check (if play is suspected):
* Pry Bar Test (Use Caution): This is more advanced and requires care to avoid damage. Gently insert a pry bar between the hub and the suspension component (being careful not to damage anything). Attempt to move the hub. Significant movement indicates a serious bearing problem. Be extremely cautious with this step, as excessive force can damage components.
5. Interpretation:
* No play, smooth rotation, and no noise: The bearing is likely in good condition.
* Play, rough rotation, or unusual noise: The bearing is likely worn and needs replacement. Replacing rear wheel bearings is generally a more involved job than replacing front wheel bearings and often requires specialized tools.
Important Considerations:
* Professional Help: If you're unsure about any step or find excessive play or damage, take your Blazer to a qualified mechanic. Replacing wheel bearings is a relatively complex task, requiring proper tools and expertise.
* Lubrication: While you can't lubricate a sealed bearing, inspecting for grease leaks can indicate a problem.
* ABS Sensors: Be mindful of the ABS (Anti-lock Braking System) sensor, which is often located near the wheel hub. Avoid damaging it during inspection.
This information is for guidance only. Always consult your vehicle's repair manual for specific instructions and torque specifications. Working on your vehicle involves inherent risks; proceed with caution and prioritize your safety.
