# Free Louisiana CDL Air Brakes Practice Test 2023

Do you need an Air Brakes endorsement or an L endorsement for your commercial driving license? The Louisiana 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 Louisiana CDL Book. 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 Louisiana CDL Practice Test to get ready to pass the Louisiana CDL Air Brake Test now.

Our CDL practice tests:
Based on 2021 LA commercial driver's license manual
Perfect for first-time, renewal applicants
LA CDL Air Brakes Test format:
25 questions
80% passing score
List of questions
1.
The safety valve discharges automatically at the pressure of:
2.
An air compressor can be cooled by _______.
3.
How far should manual slack adjusters move before they need to be adjusted?
4.
In case of a low air situation, the spring brakes should come on at:
5.
Total stopping distance for air brakes is longer than that for hydraulic brakes due to ______ distance.
6.
Spring brakes will generally come on at:
7.
The supply pressure gauge shows how much pressure:
8.
Normally during anti-lock braking, the driver:
9.
When parking a vehicle with a modulating control valve ________.
10.
If the air compressor should develop a leak, what keeps the air in the tanks?
11.
It is not safe to drive a vehicle that has brake drums with cracks that are longer than _____ of the width of the friction area.
12.
The safety valve reduces pressure at ___ psi.
13.
If the low air pressure warning light comes on, you should:
14.
15.
If air pressure is not built up within the correct amount of time, then:
16.
In a dual air brake system, the first system, supplying the rear brakes, is commonly known as the "primary" system, and the other as the:
17.
To stop the vehicle, the brake shoes and linings are pushed against:
18.
Why does a heavily loaded vehicle need a longer distance to stop?
19.
The air tanks must be drained because:
20.
If your vehicle has an alcohol evaporator, the evaporator's purpose is to _____.
21.
On newer vehicles, the parking brake control knob is typically yellow, but on older vehicles, the parking brake might be what color?
22.
What is used to put alcohol into the system and reduce ice risk?
23.
What is the purpose of a supply pressure gauge?
24.
What is a wig wag ?
25.
If your brakes are wet, what should you do to dry them quicker?