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Free CDL - Section 6 - Combination Vehicles

You are about to take a FREE Sample of the CDL - Section 6 - Combination Vehicles. The sample test consists of 10 multiple choice questions and answers.

Please select the best answer for each question below and then click "Grade It!"

1. Railroad-highway crossings often also cause problems when pulling trailers with ________________ underneath clearance.
a.
wide
b.
narrow
c.
low
d.
high
e.
None of the above
2. If you get stuck on railroad tracks, the first thing to do is:
a.
get out of the vehicle
b.
check for emergency notification at the crossing
c.
dial 911
d.
locate identifiable landmarks
3. The earliest and best way to recognize that the trailer has started to skid is by __________________.
a.
seeing it in your mirrors
b.
listening for the skid
c.
hearing it from other drivers
d.
watching steering wheel movements
4. If there is more than one trailer, the rear wheels of the ______________ trailer will offtrack the most.
a.
first
b.
middle
c.
last
d.
All of the above
5. If a trailer does not have spring brakes, use ________________ to keep the trailer from moving.
a.
wheel chocks
b.
the hand valve
c.
straight brakes
6. The tractor protection valve will close automatically if air pressure is ______________.
a.
too high
b.
too low
c.
within the optimal range
d.
None of the above
7. The trailer air supply control on newer vehicles is a ____________________.
a.
red eight-sided knob
b.
black round button
c.
red indicator light
d.
two-way switch
e.
None of the above
8. You would push the trailer air supply control in to:
a.
supply the trailer with air
b.
shut the air off
c.
put on the trailer emergency brakes
9. Tractor protection valve controls or "emergency" valves on older vehicles _______________ operate automatically.
a.
sometimes
b.
always
c.
never
10. Which one of the following is true about ABS?
a.
ABS is a replacement for normal brakes.
b.
ABS increases your normal braking capability.
c.
ABS decreases your normal braking capability.
d.
ABS only activates when wheels are about to lock up.
e.
All of the above