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
8. The easiest way to recognize that your trailer has begun to skid is to:
Explanation
The easiest way to spot a trailer skid is to use your mirrors. Any time you brake hard, check your mirrors to ensure that your trailer is still in its proper position.
9. If your trailer goes off course while you are backing, you should:
Explanation
If your trailer goes off course while you are backing, you should pull your truck forward and reposition your vehicle as needed before continuing to back up.
10. If you are operating a vehicle built before 1998 and are unsure if the trailer has an Anti-Lock Braking System (ABS), you can:
Explanation
If you are operating a vehicle built before 1998 and are unsure if the trailer has an Anti-Lock Braking System (ABS), you can check under the trailer for wheel speed sensors coming from the back of the brakes.
11. If oil and water build up in your vehicle's air tanks, the brakes:
Explanation
Air tanks should be drained daily to remove water and oil buildup. An excess of oil and water in the air tanks can interfere with proper brake function.
12. Large combination vehicles take the longest amount of time to stop:
Explanation
Large combination vehicles take longer to stop when they are empty than when they are loaded. The decreased weight causes a vehicle's wheels to have decreased traction on the surface of the road.
13. If a trailer begins to skid, the driver should:
Explanation
If your trailer starts to skid while you are braking, you should release the brakes and allow them to begin to regain traction. Once its wheels have regained their grip on the road, the trailer will begin to straighten out and follow the tractor.
14. Combination vehicles:
Explanation