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

8. What is off-tracking?

When a vehicle’s front wheels follow a different path than its rear wheels

When a vehicle's wheels all follow the exact same path

When a load shifts during a turn

When a vehicle's wheels run over a curb during a turn

When a vehicle goes around a corner, the rear wheels follow a different path than the front wheels. This is known as off-tracking, or "cheating."

9. A trailer will be most likely to swing around when:

It is full.

Traveling in a straight line.

It is empty.

The wheels are rotating.

An empty trailer will require a longer stopping distance than a loaded trailer. Additionally, a trailer is most likely to swing out and strike other vehicles when it is lightly loaded or empty.

10. The trailer hand valve:

Should always be used for parking.

Should only be used for parking on a downhill.

Should never be used for parking.

Should only be used when transporting cargo.

The trailer hand valve should not be used for parking. This could cause all of the air to leak out of the braking system, resulting in the brakes releasing. Instead, use the parking brake.

11. While inspecting a coupling, you should go under the trailer and:

Detach the jaws from around the kingpin.

Make sure the locking lever is in the "emergency" position.

Remove the safety latch.

Look into the back of the fifth wheel.

While inspecting a coupling, you should go under the trailer and look into the back of the fifth wheel. Ensure that the fifth wheel jaws are secured around the shank of the kingpin.

12. What happens when the wheels of a trailer lock up?

The trailer will usually continue to move in a straight line.

The trailer will disengage.

The trailer will likely swing around.

The trailer will stop.

A trailer tends to swing around, potentially resulting in a trailer jackknife, if its wheels lock up.

13. After finishing a pre-trip inspection, you should:

Leave the rear shut-off valves open.

Remove the service line valve.

Close the emergency line valve.

Leave the emergency line valve open.

Before a trip, you should ensure that air reaches all air brakes on all trailers by opening up the rear emergency line and service line shut-off valves to listen for escaping air. Close both shut-off valves before beginning to drive.

14. Proper coupling technique:

Is the same on all vehicles.

Is essential to the safe operation of a vehicle.

Includes ensuring that the fifth wheel plate is not greased.

Can be learned over time.

Knowing proper coupling and uncoupling technique is fundamental to the safe operation of combination vehicles. Improper coupling can be very dangerous.

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