For 1990-2009 cars only
- Block the wheels.
- Start the engine.
- Charge the system air pressure to the governor cut-out point.
- Push in the system park knob (1).
- Pull out the tractor park knob (1) and release the brake pedal.
- Apply a soap solution to the exhaust port.
- Check for leakage. Slight leakage is permitted. If leakage is excessive, replace the valve.
- Push in the tractor park knob (1).
- Check for leakage at the exhaust port. Slight leakage is permitted. If leakage is excessive, replace the valve.
- Set the parking brake.
- Remove the wheel blocks.
