Front Hub And Bearing

DIAGNOSIS AND TESTING - HUB AND BEARING - NOISE

NOTE: The wheel bearing is designed to last for the life of the vehicle and requires no type of periodic maintenance.
Bearings will produce noise if worn or damaged. The noise will generally change when the bearings are loaded. A road test of the vehicle is normally required to determine if there is a bearing noise, or if it may be some other component, and to assist in finding the location. The following procedure, together with the DIAGNOSTIC CHART, should help determine the proper cause. Note that if a particular vehicle road test maneuver, steering to the right for instance, results in noise only part of the time, it is not likely a faulty bearing. Bearing noises are not typically intermittent.
Damaged bearing seals and the resulting excessive grease loss may also require bearing replacement. Moderate grease seepage from the bearing is considered normal and should not require replacement of the wheel bearing. Wheel bearings are designed to last the life of the vehicle and require no type of periodic maintenance. To diagnose the hub, measure hub runout Testing and Inspection

DIAGNOSTIC PROCEDURE:

1. Perform drive evaluation. Find a smooth level road surface void of traffic or obstructions. Turn off any accessories which may cause background noise. Evaluate for noise at 50 km/h (30 mph) and 100 km/h (60 mph) and with vehicle in neutral to eliminate potential drivetrain noises. With vehicle at a constant speed, steer back and forth to left and right (approximately 45 degree steering input each way). This will load and unload the bearings and may change the noise level. When bearing damage is slight, the noise is sometimes noticeable at lower speeds and at other times is more noticeable at higher speeds.
2. Drive evaluation results: Noise increase when turning right may indicate a problem with the left bearing. Noise increase when turning left may indicate a problem with the right bearing.
3. Raise and support vehicle on a hoist. Grab the tire by pushing in on the top center and pulling out on the bottom center to check for excessive movement in the bearing.
4. Check for potential rubbing on rotating components, such as rotor splash shields, heat shields touching propshaft or halfshaft, wheel well liners contacting tire, wheel cover on wheel, etc. Any cyclic noise (once per wheel revolution for example) is not likely a wheel bearing fault.
5. Remove the wheel and tire assembly, disc brake caliper and brake rotor.
6. Rotate the wheel hub, checking for resistance or roughness.
7. Any roughness or resistance to rotation may indicate dirt intrusion or a failed hub bearing. If the bearing exhibits any of these conditions, the hub & bearing will require replacement. Do not attempt to disassemble the bearing for repair.
8. Rotate the wheel hub, utilize Chassis Ears (or equivalent) to check for noise.
9. If none of the above checks indicate a bearing failure, refer to the DIAGNOSTIC CHART for other possible causes.DIAGNOSTIC CHART - HUB & BEARING