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

1. Excessive use of the service brakes results in overheating. Too much heat can:

cause the brakes apply unevenly.
cause the brakes to grab.
make the brakes stop working.
cause the brakes to squeak.

2. When the wheels of a trailer lock up:

the trailer will tend to swing around.
ABS will increase stopping power.
the vehicle will gradually come to a complete stop.
All of the above.

3. When meeting an oncoming vehicle at night, if the other driver does not put their low beams on, you should:

slow down and look straight ahead in your lane.
"get back at the other driver" by putting your own high beams on.
flash your high beams at the other driver.
look slightly to the right to avoid looking directly at the lights of the oncoming vehicle.

4. When using a fire extinguisher, you should stay:

at least 10 feet away from the fire.
at whatever distance you think is safe.
as close to the fire as possible, without getting burnt.
as far away from the fire as possible.

5. The Johnson bar is a valve that:

is installed in the first tank the air compressor pumps air to.
reduces the braking pressure to a safe level.
works the trailer brakes.
keeps air from going out if the air compressor develops a leak.

6. The air storage tanks:

stop the compressor from pumping air.
are connected to the engine through gears or a v-belt.
are used to hold compressed air.
protects the tank and the rest of the system from too much pressure.

7. Emergency brakes must be held on by:

8. 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.

9. While driving, you should use your mirrors to:

check the condition of the tires and cargo.
check where the rear of your vehicle is while you make turns.
know where other vehicles are around you.
All of the above.

10. In air-operated disc brakes, the pressure of the ______ on the ______ turns a "power screw".

slack adjuster; tie rod
brake camshaft; tie rod
slack adjuster; cam roller
brake chamber; slack adjuster

AIR BRAKES PRACTICE TEST - WYOMING