Free Georgia DMV CDL — Air Brakes Practice Test 2026
The Georgia CDL — Air Brakes knowledge test has ~25 questions, and you need ~20 correct (80%) to pass. Practice free with questions written from the official Georgia driver handbook — every one has a clear explanation, and you can retake as often as you like with no sign-up.
Content reviewed against official driver handbooks · August 12, 2026
What's on the Georgia written test
The Georgia CDL — Air Brakes knowledge test has ~25 questions; you need ~20 correct (80%) to pass.
Based on the official Georgia exam format — always confirm current details with your state DMV.
Practice by topic
Focus on one area at a time — each topic has its own set of Georgia practice questions.
Following distance, scanning, blind spots, using your lights, and the habits that prevent crashes and keep you in control.
Choosing a safe speed, keeping a space cushion, adjusting for weather and traffic, and understanding stopping distance.
What to do when things go wrong — brake failure, tire blowouts, skids, and stalling on railroad tracks.
How to pass the first time
- Read the official Georgia driver handbook at least once before test day.
- Practice by topic to find your weak spots, then fix them.
- Take full-length practice tests until you pass comfortably every time.
- Read every explanation — understanding beats memorizing.
Georgia CDL — Air Brakes test — frequently asked questions
How many questions are on the Georgia CDL — Air Brakes test?
The Georgia CDL — Air Brakes knowledge test has ~25 questions, and you need ~20 correct (80%) to pass. Our practice tests mirror that format.
How many questions can I miss on the Georgia CDL — Air Brakes test?
You can miss up to ~5 of the ~25 questions and still pass — you need ~20 correct, which is 80%.
Can I retake the practice test?
Yes — practice as often as you like, completely free. The questions and answer choices are shuffled each time.
Can I take the Georgia practice test in Spanish?
Yes. Every question here is available in English and Spanish — switch languages anytime. Many states also offer the real knowledge test in languages other than English; confirm what Georgia offers with your DMV.
Can I practice on my phone?
Yes. The practice tests work in any mobile or desktop browser — no app or sign-up needed — so you can study anywhere.
Are these the real DMV test questions?
No. Our questions are original, written from the current official Georgia driver handbook to match the real test's topics and style. We are not affiliated with any DMV or government agency.
What's the best way to study?
Read the Georgia driver handbook, practice by topic to target weak areas, and finish with full-length tests until you consistently pass.
Other Georgia practice tests
Take the CDL — Air Brakes test in another state
Every Georgia question is written from the official Georgia driver handbook and checked against its current edition. DMV Test Free is a free, independent study resource — not affiliated with any DMV or government agency. About DMV Test Free
Georgia CDL — Air Brakes questions with answers
20 sample questions from the Georgia CDL — Air Brakes question bank — each with the correct answer, a short explanation, and the section of the official handbook it comes from.
Show all 20 questions with answers
1. You are testing a combination vehicle with the brake pedal held fully applied and the engine off. What is the maximum acceptable rate of air loss?
Correct answer: Less than 4 psi per minute
With the brakes applied, air loss must be less than 3 psi per minute for a single vehicle and less than 4 psi per minute for a combination vehicle, measured after the initial pressure drop.
2. Unlike hydraulic brakes, air brakes do not act the instant you press the pedal. How long does the air take to travel through the lines and apply the brakes?
Correct answer: One half second or more
This delay is called brake lag. Hydraulic brakes respond instantly, but in an air system it takes one half second or more for air to reach the brakes, so brake lag distance adds to your total stopping distance.
3. How does a "Z" restriction differ from an "L" restriction on a CDL?
Correct answer: Z bars CMVs with full air brakes, while L bars CMVs with any air brakes
Georgia's list of restriction codes defines Z as 'no full air brake' and L as 'without air brakes.' The L restriction, placed after a skills test in a vehicle without air brakes, keeps the driver out of any air brake equipped CMV.
4. The correct rhythm for snub braking on a long downgrade is to:
Correct answer: Slow about 5 mph below your safe speed, release, then reapply when back at safe speed
Once you reach your safe speed, apply the brakes firmly enough to feel a definite slowdown of about 5 mph below that speed, then release. When speed climbs back to your safe speed, repeat the cycle.
5. How do you park a vehicle whose spring brakes are worked by a modulating control valve on the dash?
Correct answer: Move the lever to the end of its travel and secure it with the locking device
A modulating valve puts the spring brakes on harder the farther its lever is moved. For parking, the lever goes to the end of its travel and the locking device keeps it there.
6. When leaving your air-braked vehicle unattended, what does proper (and required) practice call for?
Correct answer: Applying the parking brakes, or chocking the wheels when the brakes are very hot or wet in freezing weather
Any time you park, use the parking brakes (with the exceptions for very hot or wet-freezing brakes, when you use wheel chocks instead). Never leave the vehicle relying only on the service brake pedal or the transmission.
7. In newer air-braked vehicles, the parking brake control is a:
Correct answer: Yellow diamond-shaped knob you pull out to apply
The parking brakes are worked by a yellow, diamond-shaped push-pull knob. Pulling it out applies the parking (spring) brakes; pushing it in releases them.
8. For a normal stop in an air-braked vehicle, the manual says to press the brake pedal so that:
Correct answer: The vehicle comes to a smooth, safe stop
For a normal stop, push the pedal down and control the pressure so the vehicle comes to a smooth, safe stop. With a manual transmission, do not push the clutch in until engine rpm nears idle.
9. What must a CDL applicant do to be licensed WITHOUT an air brake restriction?
Correct answer: Pass the air brakes knowledge test and take the skills test in a vehicle with full air brakes
To avoid the restriction, you must pass the air brakes knowledge test and complete the skills test in a vehicle equipped with a full air brake system, demonstrating the air brake inspection during the test.
10. What is the main cause of brake fade on a long downgrade?
Correct answer: Excessive heat from using the brakes too much instead of engine braking
Relying on the service brakes instead of engine braking causes excessive heat. Overheated drums expand and linings lose friction, so the brakes provide less and less stopping power — and severe overheating can cause permanent damage.
11. During the final air brake check, how do you confirm that the parking brake holds the vehicle?
Correct answer: Set it with the vehicle stopped, then tug lightly against the brake using a low gear
The parking brake test is done from a standstill: set the parking brake, then try to move off gently in a low gear. If the vehicle stays put, the brake is holding.
12. At a roadside inspection, brakes found significantly out of adjustment (push rod stroke beyond the allowed limit) can result in:
Correct answer: The vehicle being placed out of service until the brakes are fixed
Out-of-adjustment brakes are the problem found most often in roadside inspections, and excess brake slack makes a vehicle very hard to stop. When an inspector judges a vehicle unsafe, it is put out of service until it is repaired.
13. Why do air storage tanks equipped with manual drain valves need to be drained at the end of each day of driving?
Correct answer: To remove water and compressor oil that could harm the brake system
Compressed air carries water and compressor oil into the tanks. If the accumulated water and oil are not drained daily, they can build up and damage or even disable the brakes — and water can freeze in cold weather.
14. Which distance is unique to air-braked vehicles when figuring total stopping distance?
Correct answer: Brake lag distance
All drivers face perception, reaction, and braking distance. Air-braked vehicles add a fourth element — brake lag distance — because air must flow through the lines before the brakes act.
15. A driver's CDL carries an "L" restriction. What is that driver barred from operating?
Correct answer: Any commercial vehicle equipped with air brakes
Georgia's restriction code L means 'without air brakes': the driver may not operate any CMV that has air brakes. It is placed on the license when the applicant takes the skills test in a vehicle with no air brakes.
16. Your brakes have overheated and are failing partway down a mountain grade, and an escape ramp is marked ahead. What should you do?
Correct answer: Use the escape ramp — it is built to stop runaway vehicles safely
Escape ramps use loose material or an upgrade to stop a runaway vehicle safely. If your brakes fail on a downgrade, use the escape ramp — it greatly reduces the chance of injury and vehicle damage compared to any alternative.
17. Your brakes are soaked and the temperature is below freezing. How can you dry them before you park?
Correct answer: Apply the brakes gently as you drive in a low gear so they warm up and dry
Parking brakes set on very wet brakes in freezing weather can freeze and leave the vehicle unable to move. Gentle braking in a low gear warms the brakes and dries them out first.
18. Under safety regulations, the brakes on the front wheels of a truck or tractor must be:
Correct answer: In working order like the brakes on every other wheel
Working brakes are required on all wheels. Front wheel brakes provide effective stopping power under almost all conditions, and the old practice of cutting them out or limiting them is not permitted as a substitute for proper braking.
19. Your older tractor has a front brake limiting valve with a "normal" and a "slippery" setting. Current guidance says you should:
Correct answer: Keep the valve in the normal position at all times
The slippery setting cuts the air to the front brakes by half. Testing has shown front wheel braking is good under nearly all conditions, so the manual says to leave the valve in the normal position.
20. During stab braking in an emergency, when do you release the brake pedal — and when do you press it again?
Correct answer: Release when the wheels lock up; reapply fully once the wheels start rolling again
In stab braking you apply the brakes fully, release when the wheels lock up, and apply fully again as soon as the wheels start rolling. It can take up to a second for wheels to start rolling after you release.