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

1. Before driving a truck or bus with a dual air brake system, the minimum pressure in both the primary and secondary systems should be at least:

2. When a tire fails, you must:

hold the steering wheel firmly.
stay off the brake.
All of the above.

3. Older trailers do not have spring brakes. If the air supply leaks away:

the trailer will stop normally.
the ABS won't work properly.
there will be no emergency brakes.

4. Supply pressure gauges tell you:

how much pressure is in the air tanks.
when the air pressure in the tanks falls below 60 psi.
how much air pressure you are applying to the brakes.

5. Hydroplaning is more likely if:

6. If stopped on a hill, how can you start moving without rolling back?

Press on the gas pedal, even if you have to roll back a little.
Release the parking brake before you have applied enough engine power to keep from rolling back.
Partly engage the clutch before you take your right foot off the brake, put on the parking brake if necessary.

7. 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.
You may not notice a major leak in the service line until you try to put the brakes on.
The air could leak out of the trailer air tank, releasing its emergency brakes.

8. The safety valve is usually set to open at:

9. Too little weight on the driving axles can cause:

10. Which of the following is not a type of retarder?

AIR BRAKES PRACTICE TEST - ARIZONA