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 Illinois Commercial Driver's License Study Guide. 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. After finishing a pre-trip inspection, you should:
Explanation
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.
16. To lower the risk of a rollover, you should:
Explanation
To lower the risk of a rollover, load your cargo as closely to the ground as possible. To further reduce this risk, take curves and corners slowly.
17. The trailer hand valve should be used:
Explanation
The trailer hand valve should be used only to test the trailer brakes. It should not be used while driving because it may cause the trailer to skid.
18. When glad hands are coupled, the seals should be pressed together at an angle of:
Explanation
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.
19. When driving a bobtail tractor, you should be aware that:
Explanation
Bobtail tractors are tractors that are not attached to any semitrailers. When operating a bobtail, you should be aware that stopping can be difficult and that it will take a longer distance to bring the bobtail to a complete stop than it would a tractor attached to a loaded semitrailer.
20. To prevent a trailer from rolling over, you should:
Explanation
