Instructions

Double

This endorsement is required if the driver will pull two or three trailers. To receive this endorsement, applicants must pass a test. The test consists of 20 multiple choice.. Read More

This endorsement is required if the driver will pull two or three trailers. To receive this endorsement, applicants must pass a test. The test consists of 20 multiple choice questions. To pass, the applicant must answer at least 16 questions correctly. Test questions come from the Michigan Commercial Driver License Manual. Questions come from chapters covering: Driving Safely, Air Brakes (if applicable), Combination Vehicles and Doubles and Triples. The Double/Triple endorsement can be used with the Class A CDL.

Number of Question 20

Passing Score 16

1. Look into the back of the fifth wheel:

While testing your air brakes.

If your vehicle begins to skid.

When inspecting a coupling.

While inspecting a coupling, you should go under the trailer and look into the back of the fifth wheel. Ensure that the fifth wheel jaws are secured around the shank of the kingpin.

2. What does the vehicle inspection report do?

Inform the motor carrier about problems that may need fixing

Ensure that the vehicle is inspected regularly

Keep people accountable for inspecting the vehicle

A vehicle inspection report keeps the carrier informed about any problems that need to be fixed.

3. As part of the vehicle inspection test, you will be asked to:

Explain why you must check the items you are checking.

Change the coolant.

Replace a headlight.

During the vehicle inspection test, you will be asked to do a complete inspection of your vehicle. You will need to explain what you are inspecting and why.

4. Older trailers are not equipped with spring brakes. This means that if the air supply for a vehicle's air braking system leaks away:

The trailer will stop normally.

The trailer will not have brakes.

The trailer will speed up.

Older trailers do not have spring brakes. This means that if the air supply in an older trailer's air tank has leaked away, there will be no working brakes connected to the trailer and its wheels will turn freely.

5. Do not base your decision to shift gears on:

The speed of your engine (rpm).

The speed of the road (mph).

The actions of the vehicle next to you.

One way to know when it is time to shift gears is to learn your vehicle's operating rpm range. You should shift up when your engine reaches the top of that range. You can also learn which speeds each gear is good for and shift up based on your speedometer.