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The CDL general knowledge test is required to be taken by all CDL applicants. The Idaho 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 Idaho 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 ID 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. Which of the following statements about drinking alcohol is true?
Alcohol first affects judgment and self-control, which are necessary for safe driving.
Only time will sober you up.
All of the above.
2. Which of the following are key steering system parts?
Tie rod, drag link, spindle
Lug nuts, rims, tire
Leaf spring, torque rod, front axle hanger
3. Retarders:
help slow a vehicle.
reduce the need for using your brakes.
All of the above.
4. Drivers who are convicted of a second DUI offense in either a CMV or private vehicle will lose their CDL driving privileges for:
a minimum of one year.
a minimum of five years.
5. Right after it starts to rain, the road is very slippery. Why?
Because black ice may form on the road.
Because rain is very slippery.
Because the water mixes with oil left on the road by vehicles.
6. When more cargo is piled up in a truck, the center of gravity moves:
to the left side of the truck.
closer to the ground.
higher up from the road.
7. To prevent drowsiness before a trip, drivers should:
get at least 5 hours of sleep.
drive alone.
prepare the route carefully, including stopping points.
8. When making a turn you should:
honk your horn.
signal early.
make gestures to get the attention of other drivers.
9. Heights posted at bridges and overpasses:
are always accurate.
are always incorrect.
can be incorrect.
10. Before driving a vehicle with a dual air system, allow time for the air compressor to build up a minimum of ____ pressure in both the primary and secondary systems.
75 psi
50 psi
100 psi
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Number of questions: 50
Correct answers to pass:40
Passing score:80%
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