Free South Carolina CDL Air Brakes Practice Test 2023

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

Our CDL practice tests:
Based on 2021 SC commercial driver's license manual
Full answers + detailed explanations
Perfect for first-time, renewal applicants
SC CDL Air Brakes Test format:
25 questions
20 correct answers to pass
80% passing score
List of questions
Modern air brakes combine three different systems. They are the service, the parking, and the _____ brakes.
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.
Parking or emergency brakes of trucks and buses can be legally held on by ____ pressure.
Emergency stab braking is:
An air brake system is fully charged at what psi?
To stop the vehicle, air brakes systems use:
When the engine is off and the parking brake released, a single vehicle air loss rate should be less than ________ psi in one minute.
When increased application pressure to maintain the same speed becomes necessary, you should ______.
The type of brakes that clamp the rotor between the brake shoes is:
"Some air brake systems have an alcohol evaporator. What may happen if you don’t keep the proper level of alcohol?"
If the spring brakes are on, when should you push the brake pedal?
The parking brake knob is usually:
All of the following are factors in total stopping distance except:
The emergency spring brake release knob is:
In order to make contact with the brake drum, the brake pads and linings are pushed outward by the:
Brake drums (or discs) must not have cracks longer than ____ the width of the friction area.
The use of brakes on a long and steep downgrade under normal conditions is only a supplement to:
At what level will the low air warning usually take effect?
Which of the following helps the stop light switch work?
Stop light switches are necessary because ________.
Brake drums or discs _______.
How often should alcohol containers be checked during cold weather?
What does the air compressor governor control?
What is proper braking technique for drivers travelling down a hill or any other downgrade?
To check the air compressor governor's "cut in" and "cut out" pressures you need to _________.