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 possible answer choices. Test questions come from the Idaho Commercial Driver’s 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. If planning to stop on the road to unload cargo, you should:

Explanation
You should tap your brakes and flash your brake lights to warn other drivers any time you plan to slow or stop where other drivers may not expect you to do so. Use this technique when stopping on the road to unload cargo or passengers.

2. Your CDL will be revoked if:

Explanation
If your privilege to operate your personal vehicle is revoked, canceled, or suspended due to moving traffic violations, you will also lose your CDL. This does not apply if your license is revoked due to parking violations.

3. If the coolant temperature gauge goes above the highest safe temperature, you should:

Explanation
If the coolant temperature gauge goes above the highest safe temperature, you should stop driving as soon as possible and try to figure out what is wrong. There could be an issue in your vehicle that could lead to engine failure and possibly a fire.

4. Some air brake systems introduce alcohol into the system to:

Explanation
Some air brake systems contain an alcohol evaporator. An evaporator introduces alcohol into the system to help inhibit the formation of ice in cold weather.

5. Blocking is used to:

Explanation
Blocking is used in the front, in the back, and/or on the sides of a piece of cargo to keep it from sliding while the vehicle is in motion.

6. When asked to make a lane change during the driving test, you should:

Explanation
You will be asked to change lanes during the on-road driving test. When the examiner asks you to do this, you should make the necessary traffic checks and use the proper signals before changing lanes.

7. Without the proper amount of oil in its engine:

Explanation
It is essential that a vehicle's engine have adequate oil pressure. An engine can be destroyed rapidly if it is run without oil.
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