Instructions

Combination

All applicants who are applying for a Class A CDL should be prepared to take the Combination test. This test covers information found in Section 6 of the Commercial Driver License.. Read More

All applicants who are applying for a Class A CDL should be prepared to take the Combination test. This test covers information found in Section 6 of the Commercial Driver License Manual. Section 6 provides the information needed to safely operate tractor-trailers, doubles, triples, and straight trucks with trailers. The test is made up of 20 multiple-choice questions, and applicants will have one hour to correctly answer a minimum of 16 questions. The Combination test is not a replacement for the Double/Triple endorsement test.

Number of Question 20

Passing Score 16

1. The trailer hand valve should:

Be used for parking.

Be used only to test the trailer brakes.

Be used together with the brake pedal.

Be used on slippery surfaces.

The trailer hand valve works the trailer brakes but should only be used when testing them. Using it while driving could create a skid. Never use the trailer hand valve while parking because doing so may release the air pressure from the braking system, releasing the brakes that are holding the vehicle in place.

2. Which of the following types of vehicles is most prone to the “crack-the-whip" effect?

An automobile

A three-axle tractor

A bobtail tractor

A triple combination

Double and triple combinations are the most vulnerable to turning over as a result of the "crack-the-whip" effect.

3. Using the trailer hand brake while experiencing a trailer jackknife will:

Stop the skid.

Straighten the trailer.

Increase traction.

Continue the skid.

If you are experiencing a trailer jackknife, you can help your tires regain traction by releasing the brakes. Using a trailer hand brake while experiencing a skid will only cause the skid to continue.

4. Using the trailer hand valve while driving:

Will help you turn safely.

Will stop your trailer safely.

Can cause a skid.

Is impossible.

Never use the trailer hand valve while operating your vehicle. Using the trailer hand valve while driving can cause your trailer to skid.

5. Driving a combination vehicle ____ than driving a single vehicle.

Is easier

Requires more driving skill

Is better for training

Is safer in inclement weather

Driving a combination vehicle usually requires more skill than driving a single vehicle. Combination vehicles are generally longer and heavier than single commercial vehicles.

6. Simply changing lanes can cause:

A “crack-the-whip” effect, resulting in a rollover.

A trailer to straighten out.

Confusion over which lane the driver is hoping to use.

Other drivers to reduce their speed.

Due to the "crack-the-whip" effect caused by rearward amplification, changing lanes too quickly in a combination vehicle can result in a rollover.

7. Avoid needing to make sudden lane changes by:

Using your horn to encourage other drivers to move out of your lane.

Only driving slower than the posted speed limit.

Watching the road ahead while driving.

Pulling off the road and waiting when there is high traffic.

Making a sudden lane change can be dangerous when driving a combination vehicle. Avoid the need to make a sudden lane change by looking down the road for upcoming obstacles that will require you to change lanes.

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