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View All PlansStarting a career as a commercial driver involves meeting several requirements. You must be at least 18 to apply for a CDL (Commercial Driver’s License), but you won’t be allowed to drive across state lines, carry passengers, or transport hazardous materials until you turn 21. A Class A CDL allows you to drive combination vehicles, such as semi-trucks and tractor-trailers.
The official general knowledge exam is the first test you must pass in the licensing process. It consists of multiple-choice questions based on the official National CDL Manual (Iowa CDL Handbook 2025), a comprehensive resource published by the Department of Transportation (DOT). Our Free Iowa CDL Permit Practice Test can help you ace this exam on your first attempt. Train with it daily, and your knowledge will naturally improve over time.
All Class A CDL applicants must also pass a combination vehicles knowledge test. Your understanding of coupling and uncoupling procedures, commercial driving regulations, and pre-trip inspections specific to combination vehicles will be evaluated. You must score 80% or higher to pass, leaving little room for error. The practice test that you’re about to take is part of a series of Iowa CDL Combination Vehicles Practice Tests, designed to help you master this subject. All questions are based on the National CDL Manual, specifically Section 6 (Combination Vehicles).
You get unlimited attempts to train as often as you wish. If you fail a practice session, you can start a new one right away. However, we recommend checking your personal Challenge Bank™ first, as it includes helpful insights. This section automatically stores the questions you answer incorrectly so that you can practice with them later. Each question includes a detailed explanation that will help you understand the reasoning behind the correct answer. For future reference, we recommend noting this feedback in a notebook or notebook app.
Commercial driving theory is a complex subject. Whether it takes you weeks or months to master it, we highly advise against rushing. During your learning phase, you build the foundation for a lifelong career. Improve your knowledge one question at a time and use our practice tests to become a successful commercial driver.
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