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 Kansas 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 Kansas 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

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

Close the service line valve.

Remove the service line valve.

Leave the emergency line valve open.

Leave the rear shut-off valves 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.

9. 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.

10. 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.

11. If a trailer begins to skid, the driver should:

Lock the brakes.

Release the brakes.

Steer in the opposite direction.

Accelerate.

If your trailer starts to skid while you are braking, you should release the brakes and allow them to begin to regain traction. Once its wheels have regained their grip on the road, the trailer will begin to straighten out and follow the tractor.

12. 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.

13. 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.

14. What is a tractor protection valve?

A valve to keep air in the brake system should there be a bad leak

A valve that prevents the truck from being stolen

A valve that prevents the driver from going too fast

A valve that prevents the trailer from accidentally being released

In a combination vehicle with air brakes, the tractor protection valve keeps air in the tractor or truck brake system in the event of the trailer breaking away or developing a leak.

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