Signs of a worn wheel hub bearing vary in severity. Some may be difficult to detect, leading to damage before corrective action can be taken. The time frame in which damage occurs is linked to driving conditions and/or the mechanical practices that were followed at installation. Noise is a classic sign of a bad wheel bearing or wheel hub bearing.
Wheel bearings usually come in pairs of inner and outer bearings. They allow your wheels to turn freely over thousands of miles by cushioning the contact between the wheel and the spindle it sits on with frictionless bearings and lots of nice, gooey grease. This grease tends to pick up dust, dirt, and little particles of metal, even though the bearings are protected to some extent by the hub and the brake drum or disc.
Here are some indicators of a worn wheel hub bearing or other wheel-end damage
1. Snapping, clicking or popping.
2. Grinding when the vehicle is in motion
3. Knocking or clunking.
4. Humming, rumbling or growling.
5. Wheel vibration and/or wobble.
How to detect without removing the Hub compartment or Assmebly
If you just want to check your wheel bearings for wear without removing the wheels, do the following:
1. Jack up your vehicle.
2. Support it on jack stands.
Without getting under the vehicle, grasp each wheel at the top and bottom and attempt to rock it.
There should be minimal movement. Excessive play may indicate that the wheel bearing is worn and needs adjustment or replacement.
Put the gearshift in Neutral if you have an automatic transmission, or take your manual transmission out of gear.
Rotate the wheel.
Listen for any unusual noise and feel for any roughness as it rotates, which may indicate that the bearing is damaged and needs to be replaced.
Shift back into Park (for an automatic transmission) or gear (for a manual transmission) before lowering the vehicle to the ground.