1. Visually look at the bearing. You can first see its finish (or roughness). If the quality is good, you can easily see it. Further, you can hold the bearing in your hand and turn it vigorously to see whether it rotates smoothly and naturally without noise
2. Clearance measurement
The bearing wear is judged by measuring the radial and axial clearance of the bearing. Check whether the clearance between the wheel hub bearings is appropriate. If the workmanship cannot be reached, then the quality can be imagined
3. Idling test inspection
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