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The CDL general knowledge test is required to be taken by all CDL applicants. The Iowa 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 Iowa 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 IA 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 using your turn signals, you should:
signal well before you turn.
signal only if vehicles are behind you.
turn the signal off before you turn.
2. To prevent drowsiness you should:
drive with a passenger.
keep the cab warm.
eat frequently.
3. Distracted driving can cause collisions. Which of the following can distract your attention while you are driving?
Talking to passengers.
Listening to music.
All of the above.
4. If you are driving a 30 foot vehicle at 35 mph, you should leave at least _______ between your vehicle and the vehicle in front of you.
3 seconds
2 seconds
4 seconds
5. When you are driving in heavy traffic, the safest thing to do is to:
drive 10 mph below the speed limit.
drive 10 mph below the speed of other traffic.
drive at the speed of other traffic (without going at an illegal or unsafe speed).
6. If a car suddenly cuts in front of you, creating a hazard, you should NOT:
signal and change lanes to avoid the car, if possible.
slow down to prevent a crash.
stay close behind the car and honk your horn.
7. Having ABS on only the trailer:
is very dangerous.
still gives you more control over your vehicle during braking.
makes the trailer more likely to swing out.
8. How do you put on the parking brake on newer vehicles?
By move a yellow lever to the left.
By using a round yellow knob.
By pulling out a diamond-shaped yellow knob.
9. No matter how small the cargo is, it should have at least:
1 tie-down.
4 tie-downs.
2 tie-downs.
10. With an engine fire, you should:
turn the engine off as soon as possible.
not shoot foam from the vehicle’s underside.
open the hood as soon as possible.
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IA CDL Practice Test

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