Free Delaware CDL Air Brakes Practice Test 2022

Do you need a Delaware Air Brakes endorsement or an L endorsement for your commercial driving license? The CDL Air Brake 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 Delaware CDL Practice test questions are based on the Delaware 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 free CDL practice test to get ready to pass the Delaware CDL Air Brake Test now. 

Our CDL practice tests:
Based on 2022 DE commercial driver's license manual
Full answers + detailed explanations
Perfect for first-time, renewal applicants
DE CDL Air Brakes Test format:
25 questions
20 correct answers to pass
80% passing score
List of questions
1.
An air compressor can be cooled by _______.
2.
In case of emergency when driving a vehicle equipped with dual parking control valves, you should:
3.
The stop light switch:
4.
Your truck or bus has a dual air brake system. If a low air pressure warning comes on for only one system, what should you do?
5.
The ____ shows how much pressure is in the air tanks.
6.
Brake fade is caused by:
7.
The application pressure gauge shows how much air pressure you:
8.
When the engine is off and the parking brake released, a single vehicle air loss rate should be less than ________ psi in one minute.
9.
Where is the modulating control valve located on some vehicles?
10.
To stop the vehicle, air brakes systems use:
11.
Generally, air governor cut-in should be at:
12.
Another name for the brake pedal is the "foot valve", or:
13.
When checking the low pressure warning signal, it should turn on before the pressure drops below what psi?
14.
The safety valve reduces pressure at ___ psi.
15.
All of the following are factors in total stopping distance except:
16.
The emergency spring brake release knob is:
17.
Which of these is NOT a proper time to apply the parking brakes?
18.
After the initial pressure drop, air leakage for combination vehicles should be less than:
19.
Which of the following helps the stop light switch work?
20.
The braking power of the spring brakes ______.
21.
Some vehicles are equipped with a separate air tank used specifically to release the spring brakes in an emergency, called a:
22.
If air supply drops when driving, the tractor protection valve ________.
23.
Brake drums or discs _______.
24.
What is used to put alcohol into the system and reduce ice risk?
25.
What is the function of a safety valve?