In a wheel bearing inspection, which condition signifies a failure?

Loose or rough bearings are a critical issue that signifies a failure during a wheel bearing inspection. Wheel bearings are essential components that allow the wheels to rotate smoothly and support the vehicle's weight. When bearings become loose, it can lead to excessive play in the wheel assembly, causing misalignment, poor handling, and increased wear on tires and suspension components.

Roughness in the bearings indicates that they may be worn out or damaged, which can lead to further complications, such as overheating or complete bearing failure. Such conditions could result in dangerous driving situations, including wheel lock-up or loss of control while driving.

The other conditions—clear grease appearance, even tire wear, and a secure hub assembly—do not indicate failure. Clear grease is typically a sign that there is no contamination in the bearing, even wear on tires suggests proper alignment and suspension stability, and a secure hub assembly indicates that the wheel is properly mounted and there is no risk of it loosening while driving. Thus, the presence of loose or rough bearings is the definitive failure condition in this context.