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. Each question has three possible answer choices. Test questions come from the Iowa 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. Rims with welding repairs:

Are not safe to be used.

Are acceptable to be used on tires on the rear of a vehicle.

Are acceptable to be used only when carrying a heavy load.

Wheels or rims that have had welding repairs should never be used.

2. Having anti-lock brakes on only one axle:

Will not make a difference in braking.

Will provide increased control in braking.

Will likely cause the air brakes to malfunction.

If a vehicle has anti-lock brakes on just one axle, the driver will still have more control during braking than they would without any anti-lock brakes.

3. If you realize you may be running late to your destination, you should:

Speed up.

Get upset.

Deal with it and drive at a safe speed.

To reduce the risk of developing aggressive driving behavior, you should take measures to manage your stress. One strategy to do this is to simply take a deep breath and accept your circumstances if you realize you will be late to your destination.

4. Texting while driving is especially dangerous because:

It is both a mental and physical distraction.

A message may be upsetting to the driver.

People like to read and may become too engaged in their phones.

Texting while driving is particularly dangerous because it is both a mental and physical distraction to the driver. In addition to diverting a driver's mental attention away from the road, texting requires a person to remove at least one hand from the vehicle's controls.

5. After a tire has been changed, the driver should stop after a short distance to:

Check the tightness of the lug nuts.

Ensure that the tire has remained clean.

Inflate the new tire.

After changing a tire, you should stop a short distance later to recheck the tightness of the tire's lug nuts.

6. If you cannot reverse your trailer in a straight path, you should:

Swerve back and forth while backing.

Back toward the driver's side.

Back toward the passenger's side.

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.