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 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. When traveling more slowly than 40 mph, maintain at least ____ of following distance per every 10 feet of your vehicle.
Explanation
At speeds below 40 mph, you should allow at least one second of following distance for every 10 feet of your vehicle. Follow the same formula when traveling at faster speeds, then add one additional second to your following distance. Remember that larger vehicles require more space to stop than smaller vehicles.
16. A combination vehicle has:
Explanation
Combination vehicles have two air lines: a service line and an emergency line.
17. The trailer hand valve:
Explanation
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.
18. What happens when the wheels of a trailer lock up?
Explanation
A trailer tends to swing around, potentially resulting in a trailer jackknife, if its wheels lock up.
19. When connecting a converter dolly to a second or third trailer, the trailer height should be:
Explanation
When connecting a converter dolly to a second or third trailer, the trailer height should be correct. It should be slightly lower than the center of the fifth wheel.
20. Before backing your tractor under the trailer, make sure your trailer brakes are:
Explanation
