Practice question

How do you test the parking brake in a pre-trip inspection (the tug test)?

  1. Apply the parking brake, gently try to move the vehicle in low gear, and confirm the parking brake holds
  2. Apply only the foot brake
  3. Drain the supply tank and watch the gauge
  4. Push the trailer air supply valve in

Answer: A — Apply the parking brake, gently try to move the vehicle in low gear, and confirm the parking brake holds

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