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Drivers who want to drive combination vehicles must pass the combination vehicles test. The Oregon 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 Oregon CDL Manual. Take this practice test now to prepare for the actual OR CDL combination test!
1.
Foundation brakes are used:
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only with the right wheels.
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at each wheel.
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only with the front wheels.
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only with the rear wheels.
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2.
Poor weight balance:
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makes it easier to turn.
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improves handling.
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increases fuel efficiency.
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can make vehicle handling more difficult.
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3.
After a tire has been changed, you should:
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wait at least 30 minutes before driving.
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stop a short while later and check that the nuts are tight.
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decrease tire pressure.
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deflate the tire to 15 psi.
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4.
If the drive wheels begin to spin when accelerating, you should:
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take your foot off the accelerator.
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brake gently.
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set the parking brake.
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continue to accelerate.
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5.
To secure the tractor you should:
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Put on the parking brake and put the transmission in neutral.
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Connect the tractor service air-line to the trailer service glad hand.
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Check that the kingpin and the fifth-wheel are aligned.
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All of the above.
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6.
If you are being tailgated, you should:
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speed up.
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move to the left lane.
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increase your following distance.
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flash your brake lights.
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7.
Most heavy-duty vehicles use:
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pressure brakes.
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hydraulic brakes.
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air brakes.
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solid brakes.
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8.
Antifreeze:
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helps the engine only under hot conditions.
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helps the engine only when the temperature is below freezing.
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helps the engine under hot conditions as well as cold conditions.
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doesn't help the engine in any way.
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9.
After the pre-trip inspection, drivers should inspect their cargo and its securing devices again within ________ after beginning the trip.
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25 miles
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two hours
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20 miles
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50 miles
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10.
Do not use the trailer hand valve in driving because:
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of the danger of making the trailer skid.
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the trailer emergency brakes will come on.
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the brakes can overheat and lose their braking power.
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All of the above.
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