All your missed questions are saved
automatically for extra practice.
It's a practice test that's automatically made up of all your missed questions. Once you finish this test, you’ll be able to revisit your Challenge Bank™ to practice and sharpen your skills.
View All PlansAdding difficult questions to Challenge Bank™ is an exclusive Premium feature. Unlock access to 650+ exam-like questions, a Pass Guarantee, personalized study plans, and more.
View All Plans| 90-100 | => | 12% |
| 80-89 | => | 40% |
| 70-79 | => | 28% |
| 60-69 | => | 12% |
| <60% | => | 8% |
If you’re preparing to drive commercial motor vehicles (CMVs) equipped with air brakes (and most of them are), it is necessary that you pass the Illinois CDL Air Brakes Knowledge Test and the Skills Test (in an air brake-equipped vehicle). Without this qualification, your CDL will have the “L” restriction, which limits you to CMVs without air brakes. Since most CMVs (including even large school buses) are air brake-equipped, it is in your best interest to go ahead and pass the tests.
The official Illinois CDL Air Brakes Knowledge Test includes 25 multiple-choice questions. You must answer at least 16 (80%) correctly to pass. If you do not pass, you’ll need to wait at least one business day and pay a retesting fee before another attempt. Our free Illinois CDL Air Brakes Practice Tests help you avoid that delay by mimicking the actual exam, providing immediate feedback with explanations and hints for each question, and avoiding unnecessary fluff often included in less effective guides found elsewhere. Our tests also take into account the common traps, distractors, tricky wording, and double negatives often found on the official exam. With our preparatory tools, you’ll walk into the official exam ready for anything they throw at you.
Our practice tests also feature AI-powered feedback, an interactive Illinois DMV CDL Manual, and a challenge bank that remembers any question you miss. The Challenge Bank then confronts you again with the missed questions until you’ve mastered the material. Once you’ve aced this practice test, try another one from our Illinois series here: https://driving-tests.org/illinois/il-cdl-air-brake-practice-test/.
Illinois features driving landscapes that range from the Chicago metro area and I-55 corridor to long stretches of rural interstates. Grain, machinery, and manufactured goods are carried throughout the state, and air brake-qualified truckers help Illinois’s major industries thrive. These include logistics, agriculture, manufacturing, and construction, all of which rely on air brake-qualified drivers to keep goods moving safely through the Prairie State.
To further expand your opportunities, you should consider earning endorsements like N (Tanker), H (Hazardous Materials), or T (Doubles and Triples). We have Endorsement Practice Tests perfect for preparing you for this task. Try one here: https://driving-tests.org/illinois/il-cdl-hazmat-practice-test/. You might also consider preparing for the CDL Combination Vehicles Knowledge Test, which is part of the requirements for a Class A License. We have practice tests for that as well: https://driving-tests.org/illinois/il-cdl-combination-test/.
With preparation, patience, and a little Illinois grit, you’ll be ready for your knowledge tests and skills test and on the road in no time!
Driver’s Ed is - nobody wants to set foot inside the DMV. That’s why millions of learners trust us for simple, visual, effective prep.
We are an officially recognized FMCSA Entry-Level Driver Training provider and a proud partner to over 2,500 libraries. We work with safety organizations like GHSA and the National Safety Council to help create safer roads for everyone.
Our trademarked system automatically saves questions you miss, creating personalized tests that target your weak spots until you’ve mastered the material.
Get smarter as you study. Our new AI-powered feedback provides detailed, question-level insights to help you understand the why behind each answer.
Go beyond the boring black-and-white manual. Our interactive handbook lets you read, listen with an MP3 audio version, or even chat with it to find the information you need, faster.
We build our practice questions from the current 2025 IL Driver Handbook and refine them using patterns recent test‑takers report.
Driver handbook • Knowledge‑test/permit overview • Fees & ID requirements • Office/appointment info
We mirror recurring themes (e.g., right‑of‑way traps, sign look‑alikes) and use similar distractors and wording styles.
We don’t collect or publish actual test items and we’re not affiliated with DMV.
