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Practice quizzes / Iowa CDL Combination Vehicles Test Practice Questions - Iowa Commercial Driver License Combination Vehicles Test Exam / Question 106309
Practice question

What should you check on trailer air and electrical lines?

  1. Paint color only
  2. That they drag for cooling
  3. That they are tied to the driveshaft
  4. Damage, secure support, slack for turns, and no leaks

Answer: D — Damage, secure support, slack for turns, and no leaks

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

Practice more: Iowa CDL Combination Vehicles Test Practice Questions - Iowa Commercial Driver License Combination Vehicles Test Exam →
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