1. Combination vehicles are usually heavier, longer and require more driving skill than single commercial vehicles.
A. True B. False
B. False
More than half of truck driver deaths in crashes are the result of truck rollovers. Trucks turn over easier when fully loaded and are:
B. Ten times more likely to roll over in a crash than empty rigs.
The following two things will help prevent rollovers.
B. Keep the cargo as close to the ground as possible and drive slowly around turns.
When you turn suddenly while pulling doubles, which trailer is most likely to turn over?
C. The rear trailer is twice as likely to turn over as the tractor.
Why should you not use the trailer hand brake to straighten out a jackknifing trailer?
A. Because the brakes on the trailer wheels cause the skid in the first place.
What is off tracking?
C. When a vehicle goes around a corner, the rear wheels follow a different path than the front wheels.
What is a "trailer jacknife?"
A. When the wheels of a trailer lock up and the trailer swings around.
Should you swing wide to the left before starting a 90 degree turn to the right?
A. Yes
B. No
B. No
Why should you not use the trailer hand valve while driving?
B. Because of the danger of making the trailer skid.
Describe what the trailer air supply control does.
A. It is used to supply the trailer with air, shut the air off, and put on the trailer emergency brakes.
Describe what the service line is for:
B. To carry air to a relay valve that allows the trailer brakes to be applied quickly.
What are other names for the Service Air Line?
C. Control line or signal line
What is the emergency air line?
A. Air lines connecting the parking brake to the trailer brakes.
B. Air lines that control the emergency brakes of the tractor. C. Air lines that control the emergency brakes on combination vehicles.
C. Air lines that control the emergency brakes on combination vehicles.
What is the emergency air line for?
A. To engage the front brakes of the tractor in case of an emergency.
B. To engage the trailer brakes in case of air pressure loss. C. To have extra air pressure in case you need it.
B. To engage the trailer brakes in case of air pressure loss.
Why should you use chocks when parking a trailer without spring brakes?
C. Because if the air pressure leaks away or down, there will be no brakes.
To prevent rollovers, remember to:
D. All of the above
Large combination vehicles take longer to stop:
B. When they are empty
When traveling under 40 mph, you should follow other vehicles:
C. With a distance of one second for every ten feet of your vehicle length
The earliest way to notice a trailer skid is:
A. By seeing it in your mirrors
If you start a trailer skid you should:
C. Release the brakes to get traction back
The trailer hand valve should be used:
C. Only to test the trailer brakes
Which one of the following statements about tractor protection valves is NOT true?
D. When it closes it allows air to leak from the tractor line
The trailer air supply control:
D. Is a red, eight sided knob
Which one of the following is controlled by the foot brake?
A. The service air line
The service air line is controlled by:
D. All of the above
A device which connects the service and emergency air lines from the truck to the trailer is called:
D. Glad hands
When coupling the glad hands, you should NOT do the following:
C. Cross air supply lines to test them for leaks
If you cross connect the two air lines the following will result:
C. You will not have air going to the trailer brakes
The fifth wheel should be checked to see if:
D. All of the above
When coupling the trailer, back up slowly until:
A. The fifth wheel just touches the trailer
In order to supply air to the trailer, you must first:
D. Stop engine so you can hear the brakes
A king pin is:
C. A pin which locks the trailer to the tractor on the fifth wheel
