# Free Nebraska CDL Air Brakes Practice Test 2023

Our CDL practice tests:
Based on 2021 NE commercial driver's license manual
Perfect for first-time, renewal applicants
NE CDL Air Brakes Test format:
25 questions
80% passing score
List of questions
1.
To test air service brakes you should:
2.
Total stopping distance for air brakes is longer than that for hydraulic brakes due to ______ distance.
3.
Why drain water from compressed air tanks?
4.
The supply pressure gauge shows how much pressure:
5.
To stop the vehicle, air brakes systems use:
6.
When does the air compressor governor allow air to start pumping?
7.
If the low air warning comes on while you are driving, you should:
8.
9.
The safety valve reduces pressure at ___ psi.
10.
If your truck or bus has dual parking control valves, you can use pressure from a separate tank to:
11.
After the initial pressure drop, air leakage for single vehicles should be less than:
12.
The parking brake should not be used when wet in freezing temperatures, or:
13.
Pressing and releasing the brake pedal unnecessarily:
14.
If your vehicle has an alcohol evaporator, every day during cold weather you should:
15.
Repeatedly partially increasing and pressing the brake pedal may result in:
16.
How should the air leakage rate be tested?
17.
Why should you check the brake adjustment often?
18.
In tractors and straight trucks spring brakes will come on fully when the air pressure drops to what range?
19.
During a normal drive, the spring brakes are held back by _____.
20.
Spring brakes are applied:
21.
The parking brake should be used:
22.
What is the purpose of a supply pressure gauge?
23.
The spring brakes of a tractor will come on when the air pressure falls within _______.
24.
What does ABS stand for?
25.
Required on all vehicles with air brakes, what tells the driver that air pressure is too low?