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 Alaska 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 Alaska 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
Passing Score

15. Trailers built before ____ are not required to have spring brakes.

Explanation
Trailers built before 1975 are not required to have spring brakes. When parking a trailer without spring brakes, be sure to use wheel chocks to prevent the trailer from rolling.

16. If an air supply control is in its "emergency" position:

Explanation
Tractor protection controls in older vehicles may be operated by levers instead of knobs. If an air supply control is set in its "emergency" position, the air supply will be stopped and the trailer emergency brakes will be applied.

17. What is a bobtail tractor?

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

18. When testing ____, you should apply your vehicle's brakes with the hand control while moving the vehicle forward slowly.

Explanation
To test the trailer service brakes, you should first ensure that the braking system has a normal air pressure level, then release the parking brake. You should then move the vehicle forward slowly and apply the brakes with the hand control. If the trailer service brakes are working properly, you will feel the brakes activate.

19. What is the Johnson bar?

Explanation
The trailer hand valve, also called the trolley valve or Johnson bar, is used to work the trailer brakes. It should be used only to test the brakes. Using it while a vehicle is in motion could cause a skid.

20. Combination vehicles need extra space on the road because they:

Explanation
Combination vehicles need more space on the road than other commercial vehicles because they are longer and need more space to turn and stop. It is especially important to properly manage space when you are operating a combination vehicle.
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