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 Connecticut 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. When you are pulling a trailer, the air supply control lever should be in its ____ position.

Emergency

Supply

Normal

Tractor protection controls in older vehicles may be operated by levers instead of knobs. If an air supply control is set in its "normal" position, it is properly set for you to pull a trailer.

2. A shut-off valve:

Is located on the front of a trailer.

Is located on the instrument panel.

Prevents air from escaping an air brake system.

Should always be open.

Shut-off valves are used in air supply lines to control the passage of air from one trailer to another. The rear shut-off valve should always be closed to prevent air from leaving the braking system.

3. What is a bobtail tractor?

A tractor without a trailer

A tractor attached to two trailers

A tractor with a tank

Tractors without semi-trailers are referred to as bobtail tractors. Operating a bobtail tractor requires drivers to exercise caution.

4. When glad hands are coupled, the seals should be pressed together at an angle of:

30 degrees.

45 degrees.

60 degrees.

90 degrees.

When coupling, be sure to couple the proper glad hands. When glad hands are connected, the seals should be pressed together at a 90-degree angle.

5. A tractor protection valve is:

A device that keeps air in the tractor or truck brake system, should the trailer break away or develop a bad leak.

A device that prevents theft.

A device that controls fuel levels.

A device that allows the battery to recharge efficiently.

On combination vehicles with air brakes, the tractor protection valve keeps air in the tractor or truck brake system, should the trailer develop a bad leak or break away from the tractor.

6. The easiest way to recognize that your trailer has begun to skid is to:

Ask another driver.

Use your mirrors to determine if the trailer has left the lane.

Release the brake pedal and then push it down again.

Watch the jackknife warning light on the control panel.

The easiest way to spot a trailer skid is to use your mirrors. Any time you brake hard, check your mirrors to ensure that your trailer is still in its proper position.