Free North Carolina CDL Air Brakes Practice Test 2023

Do you need an Air Brakes endorsement or an L endorsement for your commercial driving license? The North Carolina CDL Air Brake test has some differences from other endorsements because your license will receive a mark of restriction if you fail the test. So having good preparation before exam day is very necessary. To ensure that our questions are relevant, all of our CDL practice test packs are based on the NC CDL Manual. Each question has a detailed explanation for you to thoroughly learn the format and the topic. Don't be afraid of having a restriction on your license. Let’s try our NC CDL Test to get ready to pass the North Carolina CDL Air Brake Test now.

Our CDL practice tests:
Based on 2021 NC commercial driver's license manual
Full answers + detailed explanations
Perfect for first-time, renewal applicants
NC CDL Air Brakes Test format:
25 questions
20 correct answers to pass
80% passing score
List of questions
1.
An automatic wig wag will rise out of your view when the pressure in your system rises above what psi?
2.
The parking or emergency brake on a heavy vehicle can only be held in position by something that cannot leak away, like:
3.
The air brake lag distance at 55 mph on dry pavement adds about ____ feet.
4.
In case of a low air situation, the spring brakes should come on at:
5.
If your truck has a properly functioning dual air brake system and minimum size air tanks, the air pressure should build up from 85 to 100 psi within how many seconds?
6.
Total stopping distance for air brakes is longer than that for hydraulic brakes due to ______ distance.
7.
The 3 individual systems of the air brakes are the service brakes, emergency brake, and:
8.
In a controlled braking emergency:
9.
In ideal conditions a truck or bus with air brakes going at 55 mph would require the stopping distance of how many feet?
10.
When you release the brakes and reduce the air pressure what makes up for that air loss?
11.
What should a driver do when the low air pressure warning signal comes on?
12.
If the spring brakes are on, when should you push the brake pedal?
13.
What must the air pressure be, at minimum, in both parts of a dual air brake system?
14.
The air compressor governor controls:
15.
Total stopping distance with air brakes is Perception distance + Braking Distance + Brake Lag Distance +:
16.
Automatic air tanks _______.
17.
Pushing the brake pedal down harder __________.
18.
In dual air systems, how long should it take air pressure to build 85 to 100 psi?
19.
In a dual air brake system, if the air pressure in one part of the system drops enough to set off the low air warning:
20.
The air tanks must be drained because:
21.
Stab braking should only be used:
22.
What does the air compressor governor control?
23.
Spring brakes are applied:
24.
Typically, at what psi does the air compressor governor stop the compressor from pumping air?
25.
If your brakes are wet, what should you do to dry them quicker?