Fault Phenomenon: BelAZ 7530 mining truck brakes drag, high driving resistance, brake drums hot.

Troubleshooting Process:
– Checked push rod: booster push rod travel adjusted too long.
– Checked piston: brake wheel cylinder piston return poor.
– Checked spring: friction pad return spring fatigued.
– Checked air system: brake valve exhaust not smooth.

Root Cause: The air-over-hydraulic booster push rod was adjusted too long, causing preload on the brake wheel cylinder even when the brake is not applied, keeping the brakes partially engaged.

Required Parts: Readjust booster push rod travel.