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 State of Delaware 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 need to correctly answer a minimum of 16 questions to pass. The Combination test is not a replacement for the Double/Triple endorsement test.

Number of Question 20

Passing Score 16

1. The best way to recognize that your trailer has begun to skid is by:

Seeing other drivers' faces.

Seeing it in your mirrors.

Feeling it.

Listening to the radio.

The earliest and best way to recognize the beginnings of a trailer skid is by seeing the trailer veer off-course in your mirrors.

2. In a double or triple combination, the ____ trailer should be directly behind the cab.

Lightest

Heaviest

Smallest

When positioning trailers in a combination, the most heavily-loaded trailer should be the closest to the tractor. The lightest trailer should be positioned in the rear.

3. Having anti-lock brakes on only one axle:

Will not make a difference in braking.

Will provide increased control in braking.

Will likely cause the air brakes to malfunction.

If a vehicle has anti-lock brakes on just one axle, the driver will still have more control during braking than they would without any anti-lock brakes.

4. To lower the risk of a rollover, you should:

Load the cargo as far forward as possible.

Load the cargo as far back as possible.

Load the cargo as low as possible.

Stack the cargo as high as possible.

To lower the risk of a rollover, load your cargo as closely to the ground as possible. To further reduce this risk, take curves and corners slowly.

5. Look for matching colors when coupling glad hands. Service lines are often:

Green.

Orange.

Red.

Blue.

When coupling glad hands, make sure to couple together matching glad hands. To help drivers avoid mistakes, color coding is sometimes used. Service lines are often coded with the color blue and emergency lines are often coded with the color red.

6. When backing up your tractor while coupling it to a trailer, the trailer brakes should be:

Deactivated.

Locked.

Unlocked.

Correctly following the steps to couple and uncouple trailers is vital to safely operating a combination vehicle. Before backing your tractor under the trailer while coupling, make sure your trailer brakes are locked.