South Carolina CDL Permit Test - Double

Number of questions: 20
Passing score: 16
Directions: This endorsement is required if the driver will pull two or three trailers. To receive this endorsement, applicants must pass a test. The test consists of 20 multiple choice questions. To pass, the applicant must answer at least 16 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: Driving Safely, Air Brakes (if applicable), Combination Vehicles and Doubles and Triples. The Double/Triple endorsement can be used with the Class A CDL.
You have made error so far
Passing grade —
4 or fewer errors
A way to prevent drowsiness is:
To drive alone
To not exercise
Get adequate sleep before the trip
Without engine oil:
The vehicle will get better gas mileage
The engine can be destroyed quickly
The ABS won’t work properly
The windshield wipers will not operate
When should the trailer hand valve be used?
To test the trailer brakes
To check the connection between the trailer and tractor
To accelerate
To test the lights on the trailer
Which of the following is not a reason for hydraulic brake failure?
Loss of hydraulic pressure
Brake fade on long hills
If using the spring brakes when hauling a heavy load, a complete stop will:
Be impossible
Take a long time
Take a short amount of time
When entering a curve, you should:
Get off the roadway
Use the shoulder
Take the vehicle out of gear
Often driving outside of your lane may be a sign of fatigue.
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