Fault Phenomenon: Caterpillar 966 wheel loader a loud impact sound is heard while driving, then one wheel cannot be driven.

Troubleshooting Process:
– Checked wheel hub gearbox: planetary gear broken or planet carrier shattered.
– Checked axle shaft: axle shaft twisted and broken.
– Checked lubrication: insufficient gear oil.
– Checked load: severe overload or impact load.

Root Cause: The wheel hub gearbox planetary gear broke due to fatigue or instantaneous impact overload, seizing the gearbox.

Required Parts: Replace wheel hub gearbox gear set or assembly.