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Practice quizzes / Iowa CDL General Knowledge Test Practice Questions - Iowa Commercial Driver License General Knowledge Test Exam / Question 106410
Practice question

What minimum tread depth is required on front steering axle tires under general CDL safety rules?

  1. 2/32 inch
  2. 3/32 inch
  3. 4/32 inch
  4. 6/32 inch

Answer: C — 4/32 inch

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

Practice more: Iowa CDL General Knowledge Test Practice Questions - Iowa Commercial Driver License General Knowledge Test Exam →
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