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Practice quizzes / Iowa CDL Combination Vehicles Test Practice Questions - Iowa Commercial Driver License Combination Vehicles Test Exam / Question 106340
Practice question

How do you ease fifth wheel locking-jaw pressure?

  1. Raise landing gear completely
  2. Disconnect only the cord
  3. Shut off trailer air supply and back gently
  4. Accelerate forward hard

Answer: C — Shut off trailer air supply and back gently

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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