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The CDL general knowledge test is required to be taken by all CDL applicants. The Illinois 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 Illinois 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 IL 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. When you have to back, you should use a helper:
when you need to back on a curved path.
whenever possible.
only when backing toward the right side.
only when you back up with a trailer.
2. If you get stuck on railroad tracks, you should:
check the engine compartment quickly.
stay in the vehicle and call for help.
get out of the vehicle and away from the tracks.
have a helper push your vehicle.
3. If you are caught in strong winds, you should:
keep a strong grip on the steering wheel and slow down or pull off the roadway.
speed up while keeping a strong grip on the steering wheel.
immediately take your foot off the accelerator.
None of the above.
4. When checking the condition of the steering system, you must:
Test what happens under braking conditions.
Visually inspect the steering mechanism.
grab the steering mechanism to test for looseness.
Check the windshield wiper arms.
5. Bracing is used to:
protect the cargo from weather.
make cargo easier to unload.
increase the height of the vehicle’s center of gravity.
prevent movement of cargo.
6. If a trailer does not have spring brakes, to keep the trailer from moving you should:
use wheel chocks.
park on a slight decline.
close the brake valve.
use the service brakes.
7. If you experience a loss of hydraulic pressure, you should do all of the following except:
Downshift
Pump the brakes
Put the transmission in Neutral
Use the parking brake
8. When a tire fails, the driver should:
stay off the brake.
drive on the shoulder.
swerve to the right.
immediately apply the brakes.
9. What is countersteering?
Driving too fast for conditions.
Staying off the brake while steering to the right to avoid an accident.
Turning the steering wheel quickly the other way after steering in an emergency situation.
Locking your wheels while turning in an emergency situation.
10. Tire load is defined as:
the minimum safe weight a tire can carry at a specified pressure.
the weight transmitted to the ground by 1 tire.
the minimum tire pressure.
the maximum safe weight a tire can carry at a specified pressure.
 
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IL CDL Knowledge Test

Number of questions: 50
Correct answers to pass:40
Passing score:80%
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