Fault Phenomenon: Caterpillar 793F mining truck a low rumbling sound comes from the wheel hub while driving, wheel hub temperature rises abnormally.

Troubleshooting Process:
– Checked bearings: tapered roller bearing clearance excessive or preload lost.
– Checked adjusting nut: lock washer failed, nut loose.
– Checked lubrication: insufficient or deteriorated gear oil.
– Checked housing: wheel hub housing deformed.

Root Cause: The wheel hub bearing adjusting nut loosened due to vibration, causing loss of bearing preload and impact wear between rollers and raceway.

Required Parts: Replace wheel hub bearing set, readjust preload and replace lock washer.