2005-2010 Scion tC & 2000-2005 Toyota Celica Rear Hub Assembly: Diagnosing Noise and Replacement

Symptoms of a Failing Rear Hub Assembly

A bad wheel hub bearing usually gives you plenty of warning before it fails completely. The most common sign is noise. Here’s what to listen and feel for:

Noises: Grinding, Humming, and Rumbling

The classic symptom of a failing hub bearing is a noise that changes with your vehicle's speed. You might hear:

• Humming or Rumbling: This is the most common sound. It's a low-pitched drone that gets louder and higher in pitch as you drive faster. Many people mistake it for loud tire noise.
• Grinding or Growling: As the bearing wears down further, the noise can become a rougher grinding or growling sound. This indicates significant mechanical damage inside the bearing.
• Clicking or Popping: A snapping or clicking sound, especially when turning, can point to excessive play in the bearing.

Pro Tip: To figure out which side is bad, find a safe, empty road and listen as you make wide turns. When you turn right, the vehicle's weight shifts to the left side. If the noise gets louder when turning right, the bad bearing is likely on the left side, and vice-versa.

Vibrations and Other Physical Symptoms

• Steering Wheel Vibration: A worn hub bearing can cause vibrations that you feel in the steering wheel, especially at constant highway speeds.
• Loose or Wandering Steering: The vehicle may feel 'loose' or less responsive, and you might notice it pulling to one side. This happens because a worn bearing allows for excessive movement, or 'play', in the wheel.
• ABS Warning Light: Since the hub assembly for these vehicles contains the ABS wheel speed sensor, a failing bearing can cause the sensor to malfunction. Excessive movement can damage the sensor or create an incorrect reading, triggering the ABS light on your dashboard.

Known Issues, TSBs, and Recalls

Searches for Technical Service Bulletins (TSBs) and recalls for the 2005-2010 Scion tC and 2000-2005 Toyota Celica did not reveal any specific issues directly targeting the rear hub assemblies. Failures of this part are generally due to normal wear and tear, contamination from water or dirt, or harsh driving conditions. There were unrelated recalls for the 2015 Scion tC suspension and optional TRD brake kits on some models, but these do not apply to the standard hub assembly in the specified year ranges.

Buying a Used Hub Assembly: What to Look For

A used OEM hub assembly can be a great value, often outlasting cheap aftermarket alternatives. Since this part is a sealed unit, you can't see the internal bearings, but you can perform several checks to assess its condition.

Physical Inspection Checklist:

1. Check for Play: With the hub assembly held firmly, grasp the flange where the wheel bolts on. Try to rock it back and forth. There should be absolutely no noticeable play or clunking. Any movement indicates a worn bearing.
2. Spin the Hub: Rotate the hub flange by hand. It should spin smoothly and silently. Listen for any grinding noises and feel for any roughness or catching spots. A good bearing feels smooth, almost like it's packed in thick grease.
3. Inspect the ABS Sensor: Look at the ABS sensor and its wiring. Ensure the wire isn't cut, frayed, or damaged. The sensor itself should be free of cracks or obvious damage. A damaged sensor will render the part useless for an ABS-equipped car.
4. Check for Corrosion: Examine the mounting surfaces and the hub body. While some surface rust is normal for a used part, avoid assemblies with deep, flaking rust, especially around the mounting points or the bearing seals. Rust trails coming from the seals can indicate water has gotten inside.

Is Mileage a Concern?

Yes. Wheel bearings are wear items, typically designed to last around 85,000 to 100,000 miles, though this can vary widely. When buying used, try to get a hub assembly from a lower-mileage vehicle if possible. A part from a car with 70,000 miles has significantly more expected life than one from a car with 150,000 miles. Always ask for the mileage of the donor vehicle.

Replacement Overview

Replacing the rear hub assembly on a Scion tC or Toyota Celica is a straightforward DIY job for someone with moderate mechanical experience. It is a bolt-on part and does not require a hydraulic press, which is needed for many other vehicles.

Key Steps:

1. Safely raise and support the vehicle and remove the wheel.
2. Remove the brake caliper and caliper bracket, and hang them securely out of the way without stressing the brake line.
3. Remove the brake rotor. If it's stuck, there are threaded holes in the rotor where you can insert two M12 bolts to push it off the hub.
4. Disconnect the ABS sensor electrical connector from the vehicle's wiring harness.
5. From behind the knuckle, remove the four bolts holding the hub assembly in place.
6. The hub may be seized to the knuckle due to rust. If so, it may require significant force with a hammer or a slide hammer to remove.
7. Clean the mounting surface on the knuckle thoroughly before installing the new hub. Applying anti-seize to the mounting surface is recommended to prevent future issues.
8. Installation is the reverse of removal.

Important Torque Specs:

Using a torque wrench is critical for safety and to prevent premature bearing failure.

Cost Comparison

Prices can vary, but here is a general breakdown of what to expect when purchasing a single rear hub assembly.

Frequently Asked Questions (FAQ)