CDL Quiz 14

1. While you check if the rear trailer is securely coupled to the front trailer, the landing gear should be
Fully raised.
Slightly raised.
Fully lowered.

2. Glad hands are used to connect the
Kingpin from the trailer to the locking jaws of the fifth wheel.
Service and emergency air lines from the truck or tractor to the trailer.
Electrical lines from the tractor to the trailer.

3. Air lines on a combination vehicle are often colored to keep them from getting mixed up. The emergency line is ____ ; the service line is ______.
Blue; red
Red; blue
Black; yellow

4. At night, when a vehicle is carrying a load that extends four feet or more beyond the rear of the body, there must be _______ at the extreme end of the load.
Red lights
A red flag
Red flags

5. You are coupling a tractor to a semi-trailer. You have backed up but are not yet under it. Before backing under the semi-trailer, you should hook up
Nothing. Back up and lock the fifth wheel.
The emergency and service air lines.
The electrical service cable.

6. A trailer is most likely to jackknife when it is
Loaded to full capacity.

7. Which of the following is true about off-tracking or “cheating?”
If there is more than one trailer, the rear wheels of the last trailer will off-track the most.
The rear wheels follow the same path as the front wheels.
Longer vehicles off-track less.

8. You are coupling a semi-trailer to your tractor but have not yet backed under it. The trailer is at the right height if
The end of the kingpin is even with the top of the fifth wheel.
It will be raised slightly when the tractor is backed under it.
The kingpin is about 1 ¼ inches above the fifth wheel.

9. When checking the trailer emergency brakes, make sure that the tractor protection control valve is placed in the _______ position.

10. Which of these statements is true?
Light vehicles need more braking power to stop than heavy ones.
Always delay braking a heavy vehicle until you have no other choice.
”Bobtail” tractors can take longer to stop than a combination vehicle loaded to the maximum gross weight.

11. 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.

12. You are visually checking the coupling of a converter dolly to the rear trailer. How much space should there be between the upper and lower fifth wheel?
There should be ½ to ¾ inch.
There should be none.
It depends on the load.

13. You are driving a 100-foot truck with double trailers at 30 mph. The road is dry. Visibility is good. You should keep at least ____ seconds of space ahead of you.

14. Which of these statements about handling doubles and triples is true?
A triple bottom rig can stop quicker than a 5-axle tractor semi-trailer because of off-tracking.
A Sudden movement with the steering wheel can result in a tipped-over rear trailer.
The rear trailer of a 100-foot triple is less likely to turn over than a single semi-trailer because of the crack-the-whip effect.

15. You are doing a walk-around inspection of a double or triple trailer rig. You should be sure that the converter dolly air tank drain valves are ______ and the pintle hook is _______.
Open; latched
Closed; latched
Open; free

16. You want to hook your combination to a second trailer that has no spring brakes. To do this without wheel chocks, you should
Supply air to the trailer air system with the tractor and then disconnect the emergency line.
Make sure the trailer will roll freely when coupling.
Hook the trailer electric cord to a portable generator for braking power.

17. Empty trucks
May have poor traction due to bouncing and wheel lockup.
Require shorter stopping distances than full ones.
Are the easiest to stop since there is no shifting cargo.

18. If you want to couple a second trailer to your combination vehicle, secure it by using
The trailer’s spring brakes and emergency air brakes.
Wheel chocks.
Either of the above, if available.

19. Which of these statements about quick steering movements and doubles/triples is true?
Countersteering is easier with doubles/triples than with most other vehicles.
You should apply the brakes at the same time that you perform quick steering movements.\
Doubles/triples flip over from quick steering movements more easily than do many other vehicles.

20. Before you can supply air to the air tanks of a second trailer, you need to
Close the shut-off valves at the rear of both trailers.
Open the shut-off valves at the rear of both trailers.
Open the shut-off valves at the rear of the first trailer and close the shut-off valves at the rear of the second trailer.