Instructions

Knowledge Test Class A

This license is required for driving any legal combination of vehicles, with a gross combination weight rating of 26,001 pounds or more, provided the GVWR of a trailer exceeds 10,000 pounds To receive this license, applicants must pass a 50-question test. To pass, applicants must answer 40 questions correctly. Each question has three possible answer choices. Test questions come from the Missouri Commercial Driver’s Manual. Questions come from chapters covering: Introduction, Driving Safely, Transporting Cargo Safely, Air Brakes (if applicable), Combination, Doubles and Hazardous Materials. Endorsements that may be used with a Class A CDL are: Hazardous materials, Tank, Passenger, HazMat and Tank, Air Brakes and School bus.

Number of Question 50

Passing Score 40

1. When starting an engine:

The brakes will lock up.

Warning lights should turn on, then quickly turn off.

Coolant temperatures should decrease.

After a vehicle is started, the warning lights and buzzers should go out after a few seconds. If the warning signals do not turn off, there may be something wrong with the vehicle.

2. Which of the following is not a good rule when using turn signals?

Signal early. Signal well before a turn or lane change.

Signal continuously. Do not cancel a signal until the turn is completed.

Don’t over-signal. If no one is near you, there is no need to signal.

When using your turn signals, you should signal well before the turn or lane change, signal continuously throughout the turn or lane change, and cancel the signal after you have completed your move.

3. Air brakes use ____ to function.

Compressed air

Liquid air

Nitrogen

Air brakes function through the use of compressed air.

4. When driving a vehicle equipped with an Anti-Lock Braking System (ABS), you should:

Always pump the brakes several times before holding down the brake pedal.

Brake normally.

Press down the brake pedal as hard as possible every time you slow or stop.

Drivers of vehicles equipped with ABS and drivers of vehicles without ABS should brake in relatively the same manner. When ABS is working properly, it automatically applies when brakes are applied in situations that may create lockup.

5. Brake linings should be:

Loose.

Free of oil.

Soft.

Brake linings should not be loose or soaked with oil or grease. They shouldn't be dangerously thin.

6. Hydroplaning happens most often when:

A vehicle is traveling faster than 60 mph.

Tire pressure is too low.

Tire tread is too deep.

Hydroplaning is most likely to occur when driving on wet roads with tire pressure that is too low and tire tread that is too worn. If there is enough water on the road, hydroplaning can occur at speeds as low as 30 mph.

7. When loading a trailer, it is important to:

Place as little weight as possible over the axles.

Place a well-balanced amount of weight over the axles.

Place weight over only the axles.

A load of cargo must be properly balanced. Placing too much weight over an axle can damage the axle and make it more difficult for you to steer. Placing too little weight over an axle can cause poor traction, also leading to difficult handling.

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