Air Brakes CDL Test (2024) - FREE WI CDL Practice Test

1. If your tires are hot, you should NOT:

once the tires have cooled down, make another stop to check the tires.
drive until you correct the cause of the overheating.
stop to let the tires cool down.
let air out of the tires so the pressure goes back to normal.

2. At passive railroad crossings, even if there are active railroad signals that indicate the tracks are clear, you must _________ to be sure it is safe to proceed.

listen, look and stop
go, look and put the transmission in neutral
go, stop and listen
stop, look, and listen

3. Which of the following is TRUE about dual air brake systems?

Each brake system has its own air tanks, hoses and lines.
A dual air brake system has 2 separate air brake systems.
most heavy-duty vehicles use dual air brake systems.
All of the above.

4. Weight that is loaded so there is a high center of gravity:

reduces the chance that the load will shift to the side or fall off.
makes a vehicle easier to handle.
causes greater chance of rollover.
All of the above.

5. If your truck has automatic transmission, you should downshift:

when you need to accelerate.
when going down grades.
whenever road conditions allow.
after entering a curve.

6. What is the best way to test the low air pressure warning signal?

Shut the engine off when you have enough air pressure, turn the electrical power on and step on and off the brake pedal to reduce air pressure to below 60 psi.
step on and off the brake pedal while the engine is running.
pump the brakes until the air pressure drops below 45 psi.
All of the above.

7. The best way to recognize that your trailer has started to skid is:

by recognizing tire failure.
by seeing it in your mirrors.
by opening the window and feeling the front of the mirror.
by feeling the brakes come on.

8. When parking a trailer without spring brakes, it is very important for safety that you use wheel chocks. Why?

if you don't use wheel chocks, supply air will be sent to the service line instead of going to charge the trailer air tanks.
The air could leak out of the trailer air tank, releasing its emergency brakes.
You may not notice a major leak in the service line until you try to put the brakes on.
None of the above.

9. To check that spring brakes come on automatically, the first thing to do is to:

release the parking brake, move the vehicle forward slowly, and apply the brakes firmly.
continue to step on and off the brake pedal until the air pressure falls to the manufacturer’s specification.
turn off the engine, release the parking brake and time the air pressure drop.
All of the above.

10. When the spring brakes are on, you should never:

decrease your speed.
change lanes.
push the brake pedal down.
upshift.

Number of questions:	25
Correct answers to pass:	20
Passing score:	80%

AIR BRAKES PRACTICE TEST - WISCONSIN

WI Air Brakes CDL Test