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
1. When coupling a trailer:
Explanation
When coupling, make sure you couple matching glad hands. They are often color-coded to help drivers avoid mistakes. Typically, blue is used for service lines and red is used for emergency lines.
2. To help prevent a rollover, cargo should be:
Explanation
If a vehicle is top-heavy, it is more likely to roll over. The weight of cargo should be positioned as low in a trailer as possible to minimize this risk.
3. When backing a trailer, you must turn the steering wheel:
Explanation
When backing a vehicle with a trailer, you must turn the steering wheel in the direction opposite of where you want to go. Once your trailer starts to turn, you should turn the steering wheel the other way to follow the trailer.
4. If you cannot reverse your trailer in a straight path, you should:
Explanation
If you need to back your trailer but cannot back up in a straight path, you should back on a curved path toward the driver's side of the vehicle. This will allow you the best possible visibility while backing.
5. 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.
6. In a double or triple combination, the ____ trailer should be directly behind the cab.
Explanation
When positioning trailers in a combination, the most heavily-loaded trailer should be the closest to the tractor. The lightest trailer should be positioned in the rear.
7. To prevent a rollover, cargo should be:
Explanation
