This free CDL practice test will focus on 30 questions related to the Air Brake portion of the Kentucky CDL exam. For this you will need to know the parts of a single and dual air brake system, how to inspect and use them. Be sure to also take the Kentucky General Knowledge and Kentucky Combination Vehicle practice tests.
1.
Why should you not fan the brakes on and off during long downgrades?
2.
What turns on the electrical stop light switch in an air brake system?
3.
If the air system should develop a leak, what will keep the air in the air tanks?
4.
In air brake equipped vehicles, you use the parking brakes when?
5.
Which of the following statements about brakes is true?
6.
The air supply pressure gauge shows the driver how much pressure
7.
Three different systems are found on modern air brake systems; service brakes, parking brakes, and the
8.
During normal operations, the parking and emergency brakes are usually held back by
9.
When a failure occurs in the service brake system, the system you need to stop the vehicle is the
10.
The most common type of foundation brake found on heavy commercial vehicles is
11.
A combination vehicle air brake system cannot leak more than ______ psi per minute with the engine off and the brakes released.
12.
The purpose of engine retarders is to
13.
Air loss in a single vehicle (not a combination unit) should not be more than ______ with the engine off and the brakes on.
14.
To use the stab braking technique during emergency braking, you
15.
When using the parking brakes or emergency brakes, what type of pressure is being used?
16.
Which brake system applies and releases the brakes when the driver uses the brake pedal?
17.
Which of the following answers is most correct about using brakes on a long and/or steep downgrade?
19.
Air brake equipped vehicles must have
20.
If your vehicle is equipped with an alcohol evaporator, every day during the winter weather you should
21.
The air loss rate for a straight truck or bus with the engine off and the brakes applied should not be more than
22.
How do you check the free play in manual slack adjusters?
23.
If your truck or bus has dual parking control valves, you can use pressure from a separate tank to
24.
The vehicle must have a warning device which comes on when the air pressure in the service air tanks falls below
25.
What will determine how effective the spring emergency brakes or the parking brakes work?
26.
A straight truck or bus air brake system cannot leak more than ______ psi per minute with the engine off and the brakes released.
27.
Which of the following is O.K. to find in the air brake system?
28.
You must make a quick emergency stop. You should brake so you
29.
If your vehicle has an alcohol evaporator, it is there to
30.
The air compressor governor controls