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 ore 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 ore more people (including the driver)t. To receive this license, applicants must pass a 50-question test. Each question has four answer choices. To pass, applicants must answer 40 questions correctly. Test questions come from the Texas Commercial Motor Vehicle Drivers Handbook. Questions come from chapters covering: Introduction, Driving Safely, Transporting Cargo Safely, Air Brakes (if applicable), Combination Vehicles, 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

15. What color is the low air pressure warning light?

Explanation
A low air pressure warning signal is required in vehicles with air brakes. The warning light is usually red and may be accompanied by a buzzer.

16. To correct a drive-wheel braking skid, a driver should do all of the following, except:

Explanation
To correct a drive-wheel braking skid, you should first remove your foot from the brake pedal to allow the locked wheels to begin rolling again. Quickly steer in the direction you want to go, then countersteer to prevent your vehicle from skidding in the opposite direction.

17. ____ is a thin layer of ice that forms on road surfaces.

Explanation
Black ice is a layer of ice that is thin and clear enough for the road to be visible through it. This makes the road look as if it is merely wet.

18. Dry bulk tanks require special care because:

Explanation
Driving with a dry bulk tank requires special care, both because dry bulk tanks have high centers of gravity and because their loads often shift in transit. Be especially careful when taking turns and curves while operating such a vehicle.

19. If your truck or trailer catches fire, you should:

Explanation
If there is a fire in your vehicle, the first thing you need to do is leave the road and stop. Park in an open area away from anything that could catch fire, such as plants or other vehicles. Do not pull into a service station.

20. Which of the following is an example of a serious traffic violation?

Explanation
Serious traffic violations include excessive speeding (15 mph or more above the posted limit); reckless driving; improper or erratic lane changes; following a vehicle too closely; traffic offenses committed in a CMV in connection with fatal traffic accidents; driving a CMV without obtaining a CDL or having a CDL in the your possession; and driving a CMV without the proper CDL class and/or endorsements.

21. During the skills test, if making a turn that requires a stop, you should:

Explanation
If you must come to a stop before making a turn during the driving skills test, you should come to a smooth stop behind any stop line, crosswalk, or stop sign. Keep your front wheels aimed straight ahead and do not let your vehicle roll. If stopping behind another vehicle, stop where you are still able to see the rear tires of the vehicle ahead of you.
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