Fault Phenomenon: Volvo heavy forklift when the transmission shifts gears, the vehicle body shakes violently, strong impact.

Troubleshooting Process:
– Checked transmission fluid: fluid quality deteriorated.
– Checked accumulator: accumulator pressure insufficient.
– Checked solenoid valves: valves actuate too quickly.
– Checked clutch: clutch clearance small.

Root Cause: Nitrogen leakage from the transmission shift accumulator causes loss of cushioning.

Required Parts: Transmission accumulator and nitrogen charging.