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- Updated for May 2025
- Based on 2025 WI commercial driver's license manual
Free Wisconsin CDL Air Brakes Test 2025
The Badger State relies on drivers with the air brake qualification in such industries as dairy farming (Wisconsin is the top cheese producer in the U.S.), manufacturing (automotive, machinery, and heavy equipment), tourism (Great Lakes, Milwaukee, and Door County), and agriculture. Passing the Wisconsin DMV CDL Air Brakes Knowledge Test is essential for maximizing these job opportunities and avoiding unnecessary restrictions on your license, waiting periods, and additional fees. Failure to pass the Wisconsin DMV CDL Air Brakes Knowledge Test means your CDL will include the restriction “L,” prohibiting you from operating commercial motor vehicles (CMVs) with air brakes and closing the door to a long list of job opportunities. Our Wisconsin DMV CDL Air Brakes Practice Tests will prepare you for passing your knowledge exam on the first attempt.
The flat plains, rolling hills, and lakefront regions of Wisconsin demand air brake-qualified drivers. Steep grades and sharp curves and weather-related challenges like fog, high wind, and heavy snowfall present additional hazards. Key transportation routes include I-90/I-94 (running east-west across the state, connecting Milwaukee, Madison, and La Crosse), I-43 (connecting Green Bay and Milwaukee), and US-51 (running north-south, passing through rural regions, forests, and hills). Because most semi-trucks, tractor-trailers, and commercial buses rely on air brakes for safe navigation, mastering air brakes and removing the air brake restriction from your CDL are vital for expanded job opportunities.
Major companies requiring the air brake qualification include Schneider National (Green Bay) and J.B. Hunt (Madison) in the trucking industry and Badger Bus (Madison) and Lamers Bus Lines (Green Bay) in the charter bus sector. In the agriculture and dairy industry, Martin’s Milk Service, Inc. and Lemke Brothers Trucking require air brake-qualified drivers. OshKosh Corporation and The Manitowoc Company in the manufacturing and heavy equipment sector rely on the same. Many school districts in Nebraska use air brake-equipped buses. Simply put, the “L” restriction severely limits your marketability.
The written Air Brakes knowledge test features multiple-choice questions based on the state’s CDL manual (Wisconsin CDL Handbook 2025) and requires a minimum passing score of 80%. Our CDL Air Brakes Practice Tests cover everything needed for the official DMV Air Brakes Knowledge Test.
With instant feedback on all our Practice Test responses and practice tests that mimic the official knowledge test, you’ll pass the knowledge test on your first attempt!
- Perfect for first-time and renewal CDL/CLP applicants, and those adding endorsements
- Triple-checked for accuracy
What you need to know
What to expect on the actual WI DMV exam
questions
correct answers to pass
passing score
List of questions (classic view)
- Which of the following can cause brakes to fade or fail?
- The tractor protection valve
- Under which conditions are front wheel brakes good?
- Which of the following will be true about your brake function if your antilock braking system (ABS) fails?
- Which of the following is NOT part of the drum brake?
- Which of the following is NOT part of the air brake system?
- When should you drain your air tanks?
- How would you check your truck's slack adjusters?
- How can you tell if your vehicle is equipped with an antilock braking system (ABS)?
- What is the best way to test your vehicle's low air pressure warning signal?
- After the initial drop, the maximum acceptable leakage rates per minute are
- What is the best way to test if your vehicle's spring brakes come on automatically?
- If the air tanks are not drained,
- Which of the following should you do before leaving your vehicle unattended?
- Which vehicles must have low air pressure warning signals?
- An antilock braking system (ABS)
- When should you use the parking brake?
- Why must you pass a knowledge test on air brakes?
- At what measurement is the safety valve USUALLY set to open?
- Spring brakes are
- Which of the following are true about a dual air brake system?
- Which of the following is NOT part of the braking process when you're driving a tractor-trailer combination vehicle with an antilock braking system (ABS)?
- The purpose of a supply pressure gauge is
- Slack adjusters are
- How do brakes work on a long, steep downgrade?
- The low air pressure warning signal will come on before the pressure in the air tanks falls below
- A low pressure warning signal is required on
- All vehicles equipped with air brakes have
- With air brake-equipped vehicles, the parking brakes should be used
- The use of air brakes on a downgrade is only a supplement to the
- Alabama: Test 1 / Test 2
- Alaska: Test 1 / Test 2
- Arizona: Test 1 / Test 2
- Arkansas: Test 1 / Test 2
- California: Test 1 / Test 2
- Colorado: Test 1 / Test 2
- Connecticut: Test 1 / Test 2
- Delaware: Test 1 / Test 2
- District of Columbia: Test 1 / Test 2
- Florida: Test 1 / Test 2
- Georgia: Test 1 / Test 2
- Hawaii: Test 1 / Test 2
- Idaho: Test 1 / Test 2
- Illinois: Test 1 / Test 2
- Indiana: Test 1 / Test 2
- Iowa: Test 1 / Test 2
- Kansas: Test 1 / Test 2
- Kentucky: Test 1 / Test 2
- Louisiana: Test 1 / Test 2
- Maine: Test 1 / Test 2
- Maryland: Test 1 / Test 2
- Massachusetts: Test 1 / Test 2
- Michigan: Test 1 / Test 2
- Minnesota: Test 1 / Test 2
- Mississippi: Test 1 / Test 2
- Missouri: Test 1 / Test 2
- Montana: Test 1 / Test 2
- Nebraska: Test 1 / Test 2
- Nevada: Test 1 / Test 2
- New Hampshire: Test 1 / Test 2
- New Jersey: Test 1 / Test 2
- New Mexico: Test 1 / Test 2
- New York: Test 1 / Test 2
- North Carolina: Test 1 / Test 2
- North Dakota: Test 1 / Test 2
- Ohio: Test 1 / Test 2
- Oklahoma: Test 1 / Test 2
- Oregon: Test 1 / Test 2
- Pennsylvania: Test 1 / Test 2
- Rhode Island: Test 1 / Test 2
- South Carolina: Test 1 / Test 2
- South Dakota: Test 1 / Test 2
- Tennessee: Test 1 / Test 2
- Texas: Test 1 / Test 2
- Utah: Test 1 / Test 2
- Vermont: Test 1 / Test 2
- Virginia: Test 1 / Test 2
- Washington: Test 1 / Test 2
- West Virginia: Test 1 / Test 2
- Wisconsin: Test 1 / Test 2
- Wyoming: Test 1 / Test 2
Your go-to, trusted source
Experience the Driving-Tests differenceBefore you see your results, discover how CDL Premium helps you:
- Real CDL Exam-Like Wisconsin QuestionsQuestions match official CDL tests
- Official FMCSA-approvedELDT Certification included
- 99.06% Verified Pass Rate vs. 49% AverageProven success, specialized for CDL drivers
Trusted by 1.15 Million drivers
