Can you replace a speed sensor on 1998 Chevy Blazer without replacing the whole hub and bearing assembly?

Yes, you can usually replace the speed sensor on a 1998 Chevy Blazer without replacing the entire hub and bearing assembly. The speed sensor is a separate component that's often bolted or clipped into the differential housing or, less commonly, into the wheel hub itself. However, it's crucial to understand that access to the sensor might require partial disassembly of the wheel hub assembly. You won't necessarily need to replace the bearings, but you'll likely need to remove the wheel, brake caliper, rotor (possibly), and potentially the ABS tone ring to get to the sensor.

Before you start:

* Identify the exact location of your speed sensor. A repair manual specific to your year and model Blazer is highly recommended. This will show you the exact location and the removal procedure.

* Gather the necessary tools. This will likely include sockets, wrenches, a torque wrench, and possibly a puller depending on the design.

* Have a replacement speed sensor on hand. Make sure it's the correct part number for your vehicle.

The process generally involves these steps (but consult your repair manual for specifics):

1. Jack up the vehicle and secure it safely on jack stands.

2. Remove the wheel.

3. Remove the brake caliper (and possibly rotor). You'll need to support the caliper to prevent stress on the brake line.

4. Access the speed sensor. This might involve removing a retaining clip, bolt, or other fastener. The sensor is often located near the differential or within the wheel hub.

5. Carefully disconnect the electrical connector from the sensor.

6. Remove the old speed sensor.

7. Install the new speed sensor, ensuring a proper fit and secure connection.

8. Reassemble everything in reverse order, tightening bolts to the manufacturer's specified torque.

9. Lower the vehicle.

10. Test the sensor. A code reader or scan tool can be used to verify the sensor is functioning correctly.

Important Considerations:

* ABS sensor: If your speed sensor is also part of the ABS system, you might need to bleed the brakes afterward.

* Difficulty: Access can be tight and challenging depending on the exact year and model.

* Damage: There's always a risk of damaging other components during the repair process. If you're not comfortable working on your vehicle, it's best to take it to a qualified mechanic.

In short: while replacing the speed sensor independently *is* possible, it often requires more than just unbolting it. Consult a repair manual for your specific Blazer model to avoid complications.