CDL Quiz 15

1. With the hand valve on, you should test the trailer brakes by opening the service line valve at the rear of the rig. When you do this, you should hear
The service brakes slowly move to the fully applied position.
Air escape from the open valve.
The emergency line valve open and release air.

2. You should check the height of the trailer before connecting a converter dolly to a second or third trailer. The trailer height is right if
The center of the kingpin lines up with the locking jaws.
The kingpin rests on the fifth wheel.
The trailer will be raised slightly when the converter dolly is backed under it.

3. The crack-the-whip effect that troubles trucks with trailers is most likely to tip over
A full trailer behind a truck.
The rear trailer of a double.
The rear trailer of a triple.

4. Which of these statements about managing space to the sides is true?
High winds are not a problem for doubles and triples.
You should avoid traveling next to others whenever possible.
Always keep your vehicle to the right side of your lane.

5. Which of these is not a good thing to do when driving on slippery roads?
Use a light touch on the accelerator and brake pedals.
Keep other traffic out of your side space.
Use the engine brake or speed retarder.

6. Converter dollies
Usually need a glad hand converter.
Often do not have spring brakes.
Have little braking power because they are small.

7. You are driving a set of doubles. A set of trailer wheels goes into a skid. Which of these is most likely to occur?
The rig will continue to move in a straight line no matter how much the steering wheel is turned.
You will have a trailer jackknife.
The rig will stay in a straight line but slide sideways.

8. What is likely to happen if the pintle hook is unlocked while the dolly is still under the second trailer?
The air lines will rupture.
The dolly tow bar may fly up.
Nothing will happen unless the rig rolls forward.

9. Some large trucks have convex or “spot” mirrors. Such mirrors
Make things look smaller and farther away than they really are.
Do not need to be checked as often as flat mirrors because they show a larger area.
Are against the law in most states.

10. How can you be sure that you supplied air to a second trailer?
Go to the rear of the second trailer and open the emergency line shut-off.
Apply the hand valve at 10 mph. You should stop in the same distance as a truck with one trailer at 5 mph.
Watch each trailer’s air gauge for a drop of 30 psi.

11. You are driving with double trailers and must use your brakes to avoid a crash. For emergency braking, you should
Push the brake pedal as hard as you can and hold it there.
Use controlled or stab braking.
Use only the trailer brakes.

12. The best way to stop all skids is to
Countersteer and accelerate.
Restore traction to the tires.
Use stab or controlled braking.

13. Driving a truck with double or triple trailers requires a driver to
Take special care in bad weather and mountain conditions.
Allow more following distance than with smaller vehicles.
Do both of the above.

14. When driving with more than one trailer, which trailer should be the first one behind the tractor?
The heaviest trailer
The lightest trailer
The shortest trailer

15. You wish to turn right from one two-lane, two-way street into another. The truck is too long to turn without swinging wide. You should turn as shown in figure.

16. The best way to take a curve in a tanker is to slow to a safe speed before entering the curve and then ____ as you go through it.
Speed up slightly
Brake lightly
Downshift twice

17. You are driving on a clear night. You must dim your headlights from high to low. You should adjust your speed so you can stop within
The distance you will travel in the next 15 seconds.
The length of your vehicle.
The distance you can see ahead.

18. Hauling liquids in tankers requires special care for the following reason(s)
High center of gravity
Liquid movement
Both of the above

19. A tank endorsement is required for certain vehicles that transport
Hazardous materials.
Liquids or gases.

20. When should the driver of a tanker that has lost its brakes use a truck escape ramp?
Only if the tank has baffles