# Free Alabama CDL Air Brakes Practice Test 2022

Do you need an Air Brakes endorsement or an L endorsement for your commercial driving license? The Alabama 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 Alabama 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 Alabama CDL practice test to get ready to pass your Alabama CDL Air Brake Test now.

Our CDL practice tests:
Based on 2022 AL commercial driver's license manual
Perfect for first-time, renewal applicants
AL CDL Air Brakes Test format:
25 questions
80% passing score
List of questions
1.
The most common type of foundation brakes are:
2.
To test air service brakes you should:
3.
Modern air brakes combine three different systems. They are the service, the parking, and the _____ brakes.
4.
The spring brakes used on the chambers in a straight truck will bring you to a stop when air pressure drops below ___ psi.
5.
The supply pressure gauge shows how much pressure:
6.
The main factor in causing brake fade is:
7.
When the air system is low ________.
8.
When checking the low pressure warning signal, it should turn on before the pressure drops below what psi?
9.
Air governor cut-out should be at around:
10.
When your brake's main air pressure is lost ________.
11.
The parking brake knob is usually:
12.
If your truck has a dual air brake system, and one of the systems is low on pressure:
13.
The air compressor governor controls:
14.
Average stopping distance under normal conditions at 55 mph is:
15.
Compared to hydraulic brakes, air brakes add how much distance to an average 55 mph stop?
16.
Controlled braking is only possible _________.
17.
At what level will the low air warning usually take effect?
18.
At minimum, a dual air system should build up to what psi in the primary and secondary systems?
19.
The braking power of the spring brakes ______.
20.
If the air compressor has its own oil supply you should do what before driving?
21.
Why should air tanks be drained completely?
22.
On a long or steep downgrade, how should vehicle speed be primarily controlled?
23.
In a dual air brake system, one system will typically control the rear brakes, and the other:
24.
What is the purpose of an air storage tank?
25.
What happens when pressure is put on the air brakes?