# 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
Perfect for first-time, renewal applicants
DE CDL Air Brakes Test format:
25 questions
80% passing score
List of questions
1.
All air brake equipped vehicles have:
2.
How far should manual slack adjusters move before they need to be adjusted?
3.
The proper use of the brakes when going down a long steep grade after selecting a proper gear is to brake until your speed is about ____ below the posted speed and release your brake.
4.
In a controlled braking emergency:
5.
The spring brakes used on the chambers in a straight truck will bring you to a stop when air pressure drops below ___ psi.
6.
If you must make an emergency stop, you should brake so you:
7.
In ideal conditions a truck or bus with air brakes going at 55 mph would require the stopping distance of how many feet?
8.
To make sure that the spring brakes come on automatically, do all of the following except:
9.
10.
When performing the controlled braking method for an emergency stop, you are _________.
11.
If the air compressor should develop a leak, what keeps the air in the tanks?
12.
If your truck or bus has dual parking control valves, you can use pressure from a separate tank to:
13.
When brakes are applied, the brake shoes will press against the:
14.
In case of air pressure loss, a mechanical means of preventing the vehicle from moving is called:
15.
To test the parking brake, stop the vehicle, put the parking brake on, and:
16.
All of the following apply if the low air pressure warning signal does not work except:
17.
Why should you check the brake adjustment often?
18.
If your vehicle has an alcohol evaporator, the evaporator's purpose is to _____.
19.
On newer vehicles, the parking brake control knob is typically yellow, but on older vehicles, the parking brake might be what color?
20.
The belt of a belt-driven air compressor should be ________.
21.
During a normal drive, the spring brakes are held back by _____.
22.
Vehicles with air brakes _________.
23.
To check the air compressor governor's "cut in" and "cut out" pressures you need to _________.
24.
The parking brake should be used:
25.
What happens when pressure is put on the air brakes?