How to Prepare for the CDL Permit Test

To get your commercial driver’s license (CDL), you first need a commercial learner’s permit (CLP). Before you can get that permit, you have to pass the CDL permit test. For most applicants seeking an unrestricted Class A CLP for tractor-trailer training, this means passing General Knowledge, Combination Vehicles, and Air Brakes knowledge tests. Each test requires a score of at least 80%. Additional tests may be required for endorsements such as Tank Vehicles, Doubles/Tripes, Passenger, School Bus, or Hazardous Materials. 

At SAGE Truck Driving Schools, we give students free access to ProDriverU, an online platform with study guides, instructional content, and practice tests designed around the core subjects covered in state CDL manuals and Class A CLP knowledge tests. 

Once you have your CLP, you may practice driving on public roads when accompanied by a qualified CDL holder who has the proper CDL class and endorsements to operate the vehicle. The supervising CDL holder must be physically present in the front seat beside the drive. 

What’s on the CDL Permit Test 

For a Class A CDL, the permit test consists of three separate knowledge tests, each covering a different area of commercial driving. 

General Knowledge 

This is the largest of the three tests and covers the broadest range of topics. Expect questions on basic vehicle operation, pre-trip and post-trip inspections, cargo securement, hours-of-service regulations, safe driving practices, and driver wellness. 

Air Brakes 

The Air Brakes test covers how air brake systems work, proper inspection procedures, and safe usage. Many test-takers find this the hardest section, so budget extra study time for it. If you score below 80% on this test, your CDL will be issued with an air brake restriction. That restriction prevents you from operating a CMV equipped with air brakes, including the tractor-trailers commonly used in Class A training.  

Combination Vehicles 

This section covers safe operation of tractor-trailer combinations, including coupling and uncoupling procedures, managing trailer sway, and rollover prevention. 

How to Study for the CDL Permit Test 

The most effective preparation strategy is straightforward: study the material, take practice tests, and repeat until your scores are consistently high. 

• Start with your state’s official CDL manual. The FMCSA CDL page has information for new CDL applicants and links to state-specific resources. Your state’s CDL manual is the primary and most authoritative study resource for its knowledge tests. Because testing procedures and wording may vary by state, always use the current manual issued by your home-state licensing agency. 

• Use ProDriverU to practice. ProDriverU is available 24/7, so you can study around your schedule. Take practice tests until your results are consistent and your scores are high. 

• Pay extra attention to Air Brakes. It’s the section most people find hardest, and a failing score carries a license restriction. 

• Study in regular sessions rather than cramming. Daily practice is more effective than a last-minute push. 

Being well prepared before you go in should help reduce test-day nerves. 

If you have questions about how to best prepare for your CDL permit test, reach out to a SAGE school location near you. The staff will be happy to help. 

Frequently Asked Questions 

What topics are covered in the General Knowledge section of the CDL permit test? 

The General Knowledge section covers basic vehicle operation, pre-trip and post-trip inspection procedures, cargo securement, hours-of-service regulations, safe driving practices, driver wellness, and a general overview of hazardous materials handling. It is the largest of the three required knowledge tests and forms the foundation for all other CDL knowledge areas. 

How long does it take to prepare for the CDL permit test? 

There is no standard preparation period. Some applicants may be ready after a few weeks of regular study, while others need more time. Continue studying until you understand the material-not just recognize practice test answers- and can consistently score above 805 on multiple practice tests. Using a structured resource like ProDriverU and taking practice tests regularly until you’re scoring 80% or higher is a reliable way to gauge readiness. Preparation time varies depending on your prior experience and how much time you can dedicate each day. 

What is the passing score for the CDL permit test? 

The passing score is 80% on each knowledge test. This is a federal requirement under 49 CFR § 383.135 and is the same in every state. 

Are there fees to take the CDL permit test, and do they vary by state? 

Yes, fees vary by state. Most states bundle the knowledge test cost into the CLP application fee. Check your state’s DMV website for current amounts. 

How SAGE Helps You Get Ready 

Learning as much as possible before you enroll will give you an advantage once training begins. When you apply to SAGE, our team helps guide you through the pre-enrollment process, including providing study materials for the permit tests, and helps coordinate the other pre-start requirements such as your DOT physical and drug screen. 

Going through our full CDL training program gives you the knowledge and skills needed to become a professional truck driver. But there’s a lot you can do on your own first, and Pro Driver U makes it easy to get started. 

To learn more about our CDL training programs, class schedules, and locations, reach out to the SAGE school nearest you.