Instructions

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.. Read More

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 have one hour to correctly answer a minimum of 16 questions. The Combination test is not a replacement for the Double/Triple endorsement test.

Number of Question 20

Passing Score 16

8. When uncoupling a trailer, landing gear should be:

Raised completely.

Lowered halfway.

Just off the pavement.

Firmly on the ground.

Landing gear, or trailer supports, should always be completely raised before a vehicle is driven. When uncoupling, landing gear should be lowered to make firm contact with the ground. If a trailer is loaded when it is being uncoupled, you should lower the landing gear and turn the crank a few additional times to remove some weight from the trailer.

9. If the trailer begins to skid, it is best to:

Release the brakes.

Accelerate.

Quickly turn the steering wheel one way, then the other.

Brake.

If your trailer begins to skid, you should release the brakes to help regain traction. Once the wheels grip the road again, the trailer will begin to straighten out and follow the path of the tractor.

10. If you need to back your trailer but cannot back up in a straight path, you should:

Back toward the passenger's side.

Back toward the driver's side.

Swerve back and forth while backing.

Always turn to your right.

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 permit you the best possible visibility while backing.

11. If your trailer begins to drift off course while you are backing, you should:

Continue trying to back up without stopping.

Turn the top of your steering wheel in the direction of the drift.

Turn the top of the steering wheel in the direction opposite of the drift.

Return the steering wheel to the 12 o’clock position.

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.

12. Rollovers happen when:

A truck driver is driving too fast.

The driver of a vehicle in front of a truck is moving to slowly.

A truck driver is driving too slowly.

ABS is working effectively.

Rollovers happen when a vehicle is driven too fast. To reduce the risk of rollover, make sure the weight of cargo is loaded low to the ground, and that you take turns and curves slowly.

13. What is another name for the service line?

The signal line

The cable line

The surplus line

The power line

The trailer service air line is also referred to as the control line or signal line.

14. How many air lines does a combination vehicle have?

One

Two

Three

Four

Every combination vehicle has two air lines: the service line and the emergency line.

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