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Practice quizzes / LA CDL Combination Practice Questions - Louisiana CDL Combination Vehicles Test Exam / Question 115332
Practice question

A trailer starts to jackknife during braking on a slick downgrade. What principle matters most?

  1. Keep all brakes locked
  2. Add hand-valve pressure
  3. Ease off enough to regain rolling traction
  4. Shift to neutral and park

Answer: C — Ease off enough to regain rolling traction

The correct answer is shown above. Try the full quiz for additional practice.

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