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Practice quizzes / Missouri CDL Combination Practice Questions - Missouri CDL Combination Vehicles Test Exam / Question 130913
Practice question

What does the tractor protection valve protect?

  1. Cargo doors from theft
  2. Landing gear from bending
  3. ABS lamp from moisture
  4. Tractor brake-system air if the trailer breaks away or leaks badly

Answer: D — Tractor brake-system air if the trailer breaks away or leaks badly

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

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