CDL Combination Test (2021) - FREE OR CDL Practice Test

1. When approaching a vehicle with a distracted driver, you should:

quickly pass the vehicle.
sound your horn.
maintain your safe following distance.
change lanes quickly.

2. Combination vehicles usually require _________ single commercial vehicles.

3. If the safety relief valve in the air brake system releases air:

the valve is fully operational.
this will supply more power to the drive wheels.
this will supply more power to the brakes.
something is wrong.

4. When inspecting the cargo, make sure it is:

piled up.
secured properly for the first 50 miles after beginning a trip.
not overloaded.
All of the above.

5. Which of the following is NOT a way to determine if your trailer is equipped with ABS (antilock braking system)?

The letters "ABS" are printed on the side of the steering wheel.
Wheel speed sensor wires are coming from the back of the brakes.
It was built after March 1, 1998.
It has yellow ABS malfunction lamps.

6. When backing a tractor under a trailer, you should:

always use the lowest reverse gear.
back at an angle.
stop before when the kingpin is locked into the fifth wheel.
All of the above.

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

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.
The air could leak out of the trailer air tank, releasing its emergency brakes.
None of the above.

8. Containerized loads:

must be inspected before and after the trip.
are generally used for freight carried part way by rail or ship.
should exceed gross weight and axle weight limits.
All of the above.

9. The front trailer supports are up, and the trailer is resting on the tractor. Make sure:

there is enough clearance between the rear of the tractor frame and the landing gear.
All of the above.
there is enough clearance between the top of the tractor tires and the nose of the trailer.
None of the above.

10. What are the two basic reasons for covering cargo?

To protect people from spilled cargo and the cargo from pilferage.
To protect people from spilled cargo and the cargo from weather.
To protect the cargo from weather and to avoid littering.
To protect the cargo from pilferage and from weather.

CDL COMBINATION PRACTICE TEST OREGON