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Drivers who want to drive combination vehicles must pass the combination vehicles test. The Missouri CDL combination test consists of 20 questions, and you'll need at least 16 correct answers to pass (80%). The test covers the combination vehicles section of the Missouri CDL Manual. Take this practice test now to prepare for the actual MO CDL combination test!
1. Before starting down a hill, you should:
release the accelerator and shift to Neutral at the same time.
slow down and shift to a lower gear.
look for an escape route.
2. You should use chocks when parking a trailer without spring brakes because:
the brakes will hold only as long as there is air pressure in the trailer air tank.
it helps prevent skids.
it is required by law.
3. At passive railroad crossings, even if there are active railroad signals that indicate the tracks are clear, you must _________  to be sure it is safe to proceed.
go, stop and listen
stop, look, and listen
listen, look and stop
4. Longer combination vehicles have the tendency to swing wide on turns. This is called:
hydroplaning.
jackknifing.
off-tracking.
5. As you approach off ramps and on ramps, remember:
that downgrades make it easier to reduce speed.
that the posted speed limit may not be safe for larger vehicles.
to always brake and turn at the same time.
6. The crack-the-whip effect:
can turn the trailer over.
can cause a vehicle to tilt.
the ends of some vehicles to drag.
7. _________ rigs are much more likely to roll over in an accident than _________ rigs.
Fully loaded ; empty
Fully loaded ; overloaded
Empty ; fully loaded
8. Livestock:
should never be carried on a trailer.
should never be kept bunched together.
can move around in a trailer and cause unsafe handling.
9. Before connecting the converter dolly to the rear trailer, make sure that:
the shut-off valves at the rear of the first trailer are open.
the trailer height is slightly lower than the center of the fifth-wheel.
the kingpin rests on the fifth-wheel.
10. Which of the following statements about off-tracking is true?
If there is more than one trailer, the rear wheels of the last trailer will off-track the most.
Longer vehicles off-track less.
When a vehicle goes around a corner, the rear wheels follow the same path as the front wheels.
 
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MO Combination Test

Number of questions: 20
Correct answers to pass:16
Passing score:80%
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