Fault Phenomenon: Komatsu D155AX dozer cab vibration increases significantly, inspection reveals oil stain on suspension cylinder.

Troubleshooting Process:
– Checked oil seal: cylinder piston rod seal aged.
– Checked rod: piston rod surface rusted or scratched.
– Checked pressure: insufficient nitrogen pressure in suspension system.
– Checked mounting: cylinder mount deformed.

Root Cause: The cab suspension cylinder piston rod oil seal aged and failed, causing damping oil leakage and loss of suspension function.

Required Parts: Replace cab suspension cylinder seal repair kit, repair or replace piston rod.