Knowledge Test Class B

This license is required for driving a single vehicle with a GVWR of more than 26,001 pounds, and a trailer not to exceed 10,000 pounds gross vehicle weight rating, or a vehicle designed to transport 24 or more people (including the.. Read More

This license is required for driving a single vehicle with a GVWR of more than 26,001 pounds, and a trailer not to exceed 10,000 pounds gross vehicle weight rating, or a vehicle designed to transport 24 or more people (including the driver). To receive this license, applicants must pass a 50-question test. To pass, applicants must answer 40 questions correctly. Each question has three or four possible answer choices. Test questions come from the Maryland Commercial Driver License Manual. Questions come from chapters covering: Introduction, Driving Safely, Transporting Cargo Safely, Air Brakes (if applicable), Pre-Trip Vehicle Inspection Test, Basic Vehicle Control Skills Test and On-Road Driving.. Endorsements that may be used with a Class B CDL are: Hazardous materials, Tank, Passenger, HazMat and Tank, Air Brakes and School bus.

Number of Question
Passing Score

1. An empty truck:

Explanation
Empty trucks require longer stopping distances than full trucks because they have less traction available.

2. When checking the power steering fluid during a vehicle inspection, you will need to do each of the following, except:

Explanation
When checking the power steering fluid during the vehicle inspection test, you must be able to indicate where the power steering fluid dipstick is located and show that there is an adequate amount of power steering fluid in the engine compartment. The fluid level must be above the refill mark.

3. A steering wheel should be held:

Explanation
A steering wheel should be held firmly with both hands, positioned on opposite sides of the wheel.

4. When leaving your vehicle, you should:

Explanation
You should always apply the parking brake when leaving your vehicle.

5. Which of the following is not part of a vehicle’s air brake system?

Explanation
Components of an air brake system include an air compressor, an air compressor governor, air storage tanks, air tank drains, an alcohol evaporator, a safety valve, a brake pedal, foundation brakes, supply pressure gauges, an application pressure gauge, a low air pressure warning signal, a stop light switch, a front brake limiting valve (on some older vehicles), spring brakes, and parking brake controls.

6. How much water needs to be on the surface of a road for a vehicle to hydroplane?

Explanation
Hydroplaning is an effect in which a vehicle's tires lose traction with the surface of the road and instead glide along a layer of water. There does not have to be much water on the road for this to occur.

7. If hydraulic brakes fail, a driver can reduce their speed by:

Explanation
If your hydraulic bakes fail, shifting into a lower gear can help slow your vehicle down.
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