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

1. In vehicles with air brakes, water and compressor oil in the bottom of the air tank:

should be drained completely.
should not be removed.
should be added regularly.
None of the above.

2. Before driving a vehicle with a dual brake brake system, the driver should:

wait at least 5 minutes before driving.
wait at least 10 minutes before driving.
allow time for the air compressor to build up a minimum of 100 psi pressure in both the primary and secondary systems.
pump the brake pedal 10 times to build pressure.

3. Empty trucks require _____ stopping distances because empty vehicles have ______ traction.

4. Which of the following is NOT TRUE? When you drive a tractor-trailer combination with ABS, you should:

monitor your tractor and trailer as you slow down, and if it is safe to do so, back off the brakes to stay in control.
use only the braking force necessary to stop safely.
brake the same way, regardless of whether you have ABS on the tractor, the trailer, or both.
drive slower to keep your vehicle in a straight line.

5. If a load is placed on one side of the trailer:

the steering axle weight will be too light to steer safely.
your brakes won't work.
making turns may be easier.
a rollover is more likely.

6. To make the brakes work, air brakes use:

7. Banked curves:

should always be avoided.
can be taken at any speed.
have a safe "design speed".
are reserved for pedestrians.

8. Vehicles with air brake systems take longer to come to a complete stop than vehicles with hydraulic brakes because of:

9. Which of the following can cause brakes to fade or fail?

Not relying on the engine braking effect
Brakes out of adjustment
Excessive use of the service brakes
All of the above.

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

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.
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.
None of the above.

AIR BRAKES PRACTICE TEST - TENNESSEE