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The CDL general knowledge test is required to be taken by all CDL applicants. The South Carolina CDL test consists of 50 questions. To pass, you must correctly answer at least 40 questions (80%). The general knowledge test covers the contents of the South Carolina CDL Manual. All CDL applicants (Class A, B and C) must study the following sections: Driving Safely, Transporting Cargo Safely, Air Brakes (if you plan to operate vehicles equipped with air brakes), Vehicle Inspection Test, Basic Control Skills Test, Road Test. In addition, the Class A CDL test will include questions based on the Combination Vehicles section. Take this CDL practice test now to prepare for the actual SC general knowledge test! To get your CDL, you must pass both the knowledge and skills tests. CDL knowledge tests include: General Knowledge, Passenger Transport, Air Brakes, Combination Vehicles, Hazardous Materials, Tanker Vehicles, Doubles/Triples, School Bus, Firefighter. Depending on what class of license (A, B or C) and endorsements you need, you must take one or more knowledge tests. A special endorsement is also required to drive certain types of vehicles. The following endorsements may be used with a Class A, B or C CDL: HazMat (H), Tank Vehicles (N), Tank Vehicles Transporting Hazardous Materials (X) and Passenger Transport (P). The School Bus endorsement (S) is only available for Class A or B CDL, and the Doubles/Triples endorsement (T) is only available for Class A driver's licenses.
1. Black ice is:
a thick layer of ice.
ice that makes the road look dry.
a thin layer of black ice.
None of the above.
2. When you exit a highway using an off ramp that goes downhill and turns at the same time, you should:
slow down to the posted speed limit for the off ramp.
slow down before you get on the curved part of an off ramp.
wait until you are in the curve curved part of the off ramp before downshifting.
get on the curved part of the off ramp, then brake and turn at the same time.
3. When you need to brake, you should warn the drivers behind:
by making gestures.
by turning on the 4-way emergency flashers.
by changing lanes.
by flashing your brake lights.
4. What is a common cause of tire fires?
Cold tires
Duals that touch
Loose lug nuts
All of the above.
5. Which of the following is NOT a type of retarder?
6. To correct a drive-wheel skid, you should NOT:
Steer into the skid.
Stop braking.
Push in the clutch.
7. The minimum tire tread depth for front tires is:
4/16 inch
8/32 inch
4/32 inch
2/32 inch
8. The air compressor governor:
controls when the air storage tanks will pump air into the air compressor.
stops the compressor from pumping air.
allows the compressor to start pumping air when the tank pressure rises to the "cut-out" pressure.
All of the above.
9. If you are confronted by an aggressive driver, you should:
remain calm and relaxed.
avoid eye contact.
try to move away safely.
All of the above.
10. The only way to stop a front-wheel skid is to:
let the vehicle slow down.
supply more power to the drive wheels.
All of the above.
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Number of questions: 50
Correct answers to pass:40
Passing score:80%
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