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 Idaho Commercial Driver's 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
8. Rollovers happen when:
Explanation
Rollovers occur when drivers turn or change lanes too quickly.
9. If you are backing and the trailer begins to drift off-course, the driver should:
Explanation
If your trailer begins to drift while you are backing, you should correct the drift immediately by turning the top of the steering wheel in the direction of the drift.
10. Combination vehicles are usually:
Explanation
Driving combination vehicles requires more skill than driving single commercial vehicles. Combinations are generally longer, generally heavier, and are more vulnerable to rollover.
11. In an empty combination vehicle, the stiff suspension springs and strong brakes will have:
Explanation
An empty combination vehicle will come to a complete stop more slowly than a fully-loaded vehicle. With less weight in a trailer, the stiff suspension springs and strong brakes will have lower traction than they would if the vehicle carried more weight.
12. 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.
13. If a load is placed on one side of a trailer, the trailer:
Explanation
Positioning the weight of a load on one side of a trailer may cause the trailer to lean to that side, increasing the risk of a rollover during turns and lane changes.
14. Combination vehicles:
Explanation