Knowledge Test Class A

This license is required for driving any legal combination of vehicles, with a gross combination weight rating of 26,001 pounds or more, provided the GVWR of a trailer exceeds 10,000 pounds To receive this license, applicants must pass a 50-question.. Read More

This license is required for driving any legal combination of vehicles, with a gross combination weight rating of 26,001 pounds or more, provided the GVWR of a trailer exceeds 10,000 pounds To receive this license, applicants must pass a 50-question test. To pass, applicants must answer 40 questions correctly. Each question has two, three or four possible answer choices. Test questions come from the South Carolina Commercial Driver License Manual. Questions come from chapters covering: Introduction, Driving Safely, Transporting Cargo Safely, Air Brakes (if applicable), Combination, Doubles and Hazardous Materials. Endorsements that may be used with a Class A CDL are: Hazardous materials, Tank, Passenger, HazMat and Tank, Air Brakes and School bus.

Number of Question
Passing Score

1. Header boards:

Explanation
A header board protects a driver from moving cargo in the event of a crash or emergency stop.

2. If an aggressive driver is involved in a crash down the road, you should:

Explanation
If you observe a crash involving an aggressive driver, you should stop a safe distance from the crash scene, wait for police to arrive, and inform them of the aggressive behavior you witnessed.

3. When inspecting underneath your vehicle for leaking fluids, you must look for all the following, except:

Explanation
When approaching your vehicle before a trip, be sure to look underneath the vehicle for fresh oil, coolant, grease, or fuel leaks.

4. Headlights:

Explanation
To improve visibility, you should use high beam headlights at night where it is safe and legal to do so. However, the glare from high beam lights can blind other drivers. You should dim your lights to their low beam setting when driving within 500 feet of an approaching vehicle.

5. In extremely hot conditions, you may have to:

Explanation
Faster speeds create more heat in the engine and tires, so slow down to avoid dangerous overheating when the weather is very hot.

6. Which of the following may result in an applicant being denied a hazardous materials endorsement?

Explanation
You will be denied a hazardous materials endorsement, or lose an existing endorsement, if you renounce your U.S. citizenship; are not a lawful permanent U.S. resident; are wanted for, indicted for, or convicted of certain felonies; are judged mentally defective or are committed to a mental institution; or are deemed by the Transportation Security Administration (TSA) to pose a security threat.

7. When traveling down a steep downgrade:

Explanation
On long and/or steep downgrades, you should primarily use engine braking to control the speed of your vehicle. Use your brakes only as a supplement to this effect.
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