Fault Phenomenon: SANY SG215 grader severe oil leak at the connection between the transmission and driveshaft.

Troubleshooting Process:
– Checked oil seal: lip worn or rolled.
– Checked shaft journal: shaft journal worn with groove.
– Checked breather: transmission breather clogged, high internal pressure.
– Checked oil level: level too high.

Root Cause: The clogged transmission breather caused high internal pressure, which pushed out or accelerated wear on the oil seal, and the worn shaft journal exacerbated the leak.

Required Parts: Replace oil seal, repair shaft journal, and clear breather.