For many people, trucking is a great career choice. If you decide to work as a truck driver, you must first obtain a Commercial Driver’s License (CDL). The trucking industry requires responsible people behind the wheel. Therefore, the CDL general knowledge test and skills test are necessary to evaluate the responsibility of the driver.

However, not everybody passes the CDL test the first time. Failure can result from many reasons. Some of the most common reasons are stress, lack of concentration, not enough time to study and prepare, inability to retain information, etc. Failing the test does not imply that you are a loser who will never be a truck driver. Accepting this will make the exam less stressful, and you will be able to learn from your mistakes.

To prepare well for the CDL exam, drivers should follow a CDL general knowledge study guide. This article will provide you the general information about the CDL general knowledge test together with some useful advice to help you pass your CDL license exam.

cdl general knowledge study guide
CDL General Knowledge study guide

1. How many questions are on the general knowledge CDL test?

The CDL General Knowledge test is a compulsory test you need to take when taking part in the CDL exam. The test has 50 multiple-choice questions. The general knowledge test covers CDL rules and requirements, safe driving, cargo transportation safety, and pre-trip vehicle inspections, among other topics. Normally, it takes you about 90 minutes to complete this test.


2. How many times can you fail the CDL general knowledge test?

If you fail the CDL knowledge test, you have to wait three calendar days before taking it again on the fourth day. If you take and fail the knowledge test on Tuesday, for example, you won’t be able to take it again until Saturday. If you fail the CDL knowledge test six times in a 12-month period, you will not be able to take the seventh test until 12 months have passed since you failed the first.

There is no limit to the number of knowledge tests you can take within the 180-day period, but there is a mandatory waiting period of seven days before you can retake the knowledge test; however, the test receipt is valid for 180 days and will need to be renewed for $125.00 upon expiration of the test receipt. The basic general knowledge test must be passed before any endorsement test can be taken. All CDL test scores are good for 360 days (written, vision and road).


3. How to pass the CDL general knowledge test?


3.1. Determine what to study for the CDL general knowledge test

The material covered on the CDL general knowledge test is nearly identical in every state, ensuring that every CDL-certified driver is fully aware of all regulations and standards regardless of the state that issued the license. Each driver who wants to get their CDL must pass the general knowledge test with an 80 percent grade. There are four different classes of CDL licenses, and which parts of the CDL manual you should study depends on the class license you are seeking and which endorsements you want to fulfill.

Your commercial driver guide will probably be drilled into your head during your training. Here are the primary things you’ll need to study and know for the CDL General Knowledge tests, in case you didn’t previously know:

  • CDL General Knowledge test – CDL Class A, B, C.
  • CDL Combination Test (Class A) – if you’re planning on tractor-trailers.
  • Air brakes.
  • Double-triple rigs.
  • Tank vehicles.
  • Hazardous materials.
  • Passenger.
  • School bus.
cdl general knowledge test study guide
CDL Knowledge test is divided into classes A,B, C

3.2. Collect study materials

There are numerous effective ways to prepare for your CDL exam. The trick is to figure out which ones are essential and which ones are enjoyable to add to your learning schedule. Below are a number of possible practice material sources and their importance:


Material Source Benefits
CDL Manual
  • This manual is the most reliable and comprehensive information source available.
Driving test apps
  • They are useful and simple to use.
  • Examples of test questions are included in the apps.
  • Some of them provide extra details.
Study guides
  • They contain material from the Manual that has been condensed.
  • Study guides contain important information on the exam procedure.
Practice tests
  • Practice tests are designed to look like real exam.
  • They make it easier for you to recall information.
  • They can be used to track your progress.
  • They include a variety of question combinations.

As you can see, each type of material has its own benefits. The best preparation method involves combining the CDL Manual and practice tests. This method not only helps you grasp information in a comprehensive way but also helps you remember general knowledge more easily.

cdl general knowledge study guide
Practice helps you pass the CDL exam easier

3.3. Practice with mock tests

CDL tests are not difficult to pass, providing that you prepare thoroughly. Although your state’s manual has all of the necessary material, you should not overlook other learning strategies. Most people fail because they are unfamiliar with the test’s structure and format, rather than because they lack basic knowledge.

Simply by searching in Google, Bing, or whatever search engine you like, you can find many sites that provide mock tests and practice exercises. Many of them are for free. One thing to keep in mind is that, while there are many, not all of them are updated. All of the trucking rules, legislation, and regulations are continually changing. You may also download practice apps for your iPhone or Android smartphone that include CDL General Knowledge practice exam questions in a variety of categories. These apps also provide you with detailed study guides that help you improve faster.

You can join CDL practice test by downloading our application (available on both IOS and Android).


3.4. Stay focused

The CDL General Knowledge tests are not the toughest tests. People who do not pay enough attention and do not devote themselves to learning, on the other hand, will perform poorly. If you study when you’re weary, you won’t be able to recall the material as well. When you don’t feel rushed, it’s convenient for you to study. If you work, you can study during your lunch break. In addition, you had better keep distractions to your phone or television, which help to increase your concentration. Train yourself to read each question and respond carefully when taking practice tests. If you don’t know the material as well as you should, there will always be a few trick questions or answers tossed in to confuse you. So take it slowly, read each word slowly and carefully, and choose the best answer.


It may only take a few weeks to go through your CDL truck driving course, but there’s a lot of information you’re going to be expected to learn. Paying attention in class at your CDL driving school, studying the Commercial driver guide, working with fellow students, and taking the tests seriously are all keys to passing the CDL General Knowledge test. With the information about the CDL General Knowledge Study Guide above, we hope that you can draw yourself a suitable study plan and succeed with the CDL exam.