Practice question

What is the correct procedure for testing trailer brakes after coupling?

  1. Apply service brakes at highway speed and note stopping distance
  2. With tractor and trailer connected, move forward slowly while applying only the trailer hand valve
  3. Apply the parking brake only and release it quickly
  4. Have a passenger watch the trailer wheels while you drive past

Answer: B — With tractor and trailer connected, move forward slowly while applying only the trailer hand valve

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