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Drivers who want to drive combination vehicles must pass the combination vehicles test. The Washington 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 Washington CDL Manual. Take this practice test now to prepare for the actual WA CDL combination test!
1. The first thing to do when coupling a tractor-semitrailer is to:
inspect the fifth wheel.
lock the trailer brakes.
check the trailer height.
2. The heavier the vehicle:
the more work the brakes must do to stop it.
the higher the center of gravity will be.
the less work the brakes must do to stop it.
3. Weight that is loaded so there is a high center of gravity:
causes greater chance of rollover.
makes a vehicle easier to handle.
reduces the chance that the load will shift to the side or fall off.
4. When backing with a trailer, you should:
check your mirrors on both sides frequently.
look at your line of travel before you begin backing.
All of the above.
5. During a trip you need to inspect the cargo and its securing devices:
after every break you take.
every 3 hours or 150 miles.
All of the above.
6. When inspecting the coupling, make sure the fifth-wheel jaws have closed around the:
shank of the kingpin.
head of the kingpin.
the electrical cord.
7. Axle weight is:
the maximum safe weight your tires can carry at a specified pressure.
the weight transmitted to the ground by one axle or one set of axles.
the weight of all the axles added together.
8. Tar in the road pavement rising to the road surface in very hot weather:
is very sticky and will slow down your vehicle.
causes the road to become very slippery.
does not affect the road surface or driving conditions.
9. To prevent rollover, you should:
drive on the shoulder of the road when possible.
drive slowly around corners.
drive in the left lane.
10. The crack-the-whip effect:
can cause a vehicle to tilt.
can turn the trailer over.
the ends of some vehicles to drag.
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WA CDL Combination Test

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