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 Louisiana Commercial Driver License Manual. Questions come from chapters covering: Introduction, Driving 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. When adjusting your mirrors before a trip:

Explanation
When properly adjusted, your mirrors should each display some part of your vehicle. Being able to see your own vehicle in your mirrors will give you a point of reference when judging the positions of other objects.

2. Air tank drains should:

Explanation
In an air brake system, air tank drains are used to remove water and compressor oil from the air tanks. When operating a drain, be sure to drain the tank completely.

3. Items on a flatbed:

Explanation
On flatbed trailers and trailers without sides, cargo must be tied down to prevent it from shifting or falling off in transit.

4. A tread depth of ____ should be in every major groove of a front tire.

Explanation
For safe operation, a commercial motor vehicle needs a tread depth of 4/32 of an inch in every major groove on the front tires, and a tread depth of 2/32 of an inch on other tires.

5. How soon after starting a trip must cargo securement be checked?

Explanation
Cargo should be inspected before beginning a trip, within the first 50 miles of the trip, and every three hours or 150 miles traveled thereafter. The driver of a truck transporting cargo is responsible for the cargo being safely secured throughout the trip.

6. The two markings on a front brake limiting valve usually read:

Explanation
Some vehicles with air brake systems manufactured before 1975 have a front brake limiting valve with "normal" and "slippery" settings.

7. Stopping distance can be affected by:

Explanation
Factors that can affect stopping distance include the vehicle's speed, its weight, and the traction provided by the road surface.
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