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Practice quizzes / Virginia CDL Combination Practice Questions - Virginia CDL Combination Vehicles Test Exam / Question 198203
Practice question

The tractor protection valve helps:

  1. Aim the headlights
  2. Grease the kingpin
  3. Protect tractor air pressure if trailer air is lost
  4. Steer the trailer axle

Answer: C — Protect tractor air pressure if trailer air is lost

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

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