Knowledge Test Class B

This license is required for driving a single vehicle with a GVWR of more than 26,000 pounds, a 3-axle vehicle weighing over 6,000 pounds, a bus (except a trailer bus), with endorsement or any farm labor vehicle, with.. Read More

This license is required for driving a single vehicle with a GVWR of more than 26,000 pounds, a 3-axle vehicle weighing over 6,000 pounds, a bus (except a trailer bus), with endorsement or any farm labor vehicle, with endorsement. To receive this license, applicants must pass a 50-question test. Each question has three answer choices. To pass, applicants must answer 40 questions correctly. Test questions come from the California Commercial Driver 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

1. You may not consume alcohol within ____ of going on duty.

Explanation
Commercial vehicle drivers are prohibited from consuming any intoxicating beverage, regardless of its alcohol content, within four hours of going on duty.

2. A tread depth of ____ should be in every major groove of a tire that is not in the front of a commercial motor vehicle.

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.

3. Why do large vehicles use air brakes?

Explanation
If used and maintained properly, air brakes are a safe and effective way to stop large, heavy vehicles.

4. When backing with a trailer, you should begin by:

Explanation
When backing with a trailer, begin by turning the steering wheel in the direction opposite of the turn. Once the trailer starts to turn, reverse the direction of the steering wheel to follow the trailer.

5. While driving downhill, you should brake until you reach a speed that is ____ below your safe speed, then release the brake pedal.

Explanation
While driving downhill, you should hold down the brake pedal until your vehicle reaches a speed 5 mph below your safe speed, then release the brake pedal. Repeat this process.

6. When backing with a trailer:

Explanation
When backing, you should pull forward to reposition your vehicle whenever needed. Drift should be corrected immediately by turning the steering wheel in the direction of the drift.

7. If involved in an accident, which of the following is not recommended?

Explanation
When involved in an accident, you should protect the area, notify authorities, care for the injured, collect required information, and report the accident. You can lose your license for leaving the scene of an accident.
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