illinois
CDL Practice Test

Welcome to the Illinois CDL Practice Test site. This is a free site and you are able to take the tests as a study guide as you prepare for the Illinois CDL test. The topics covered in these practice tests are taken from the Illinois CDL book. You will be presented with 40 questions and you must answer 34 questions correctly to pass. There is a 50-minute time limit. You may not go back once you answer a question. Click the "Start Test" button below to begin.

1 / 40

Which trailer is most likely to tip over due to the crack the whip effect?

the last trailer of a double

the heaviest trailer

the last trailer of a triple

the first trailer of a triples

2 / 40

What is the safest way to stop unruly behavior on the bus?

yell loudly for the students to sit down and behave themselves

have the unruly students move to the front of the bus

pull off the road in a safe location, secure the bus, stand up, and tell the students what behavior you expect of them

keep checking the rear view mirror so you can see what happened and report to the principal

3 / 40

You should check the_____when loading small tanks equipped with bulkheads.

expansion rate

percentage of water

distribution of the weight

fuel to air ratio

4 / 40

Which of the following statements about stopping distances is NOT true?

empty trucks require greater stopping distances because they have less traction

trucks traveling on ice or snow require greater stopping distances

trucks traveling at higher speeds require greater stopping distances

brakes, tires, springs and shocks are designed to work best when the truck is empty

5 / 40

Which of these is a good rule for backing a straight bus?

Use your head as the mirrors are unreliable.

Back toward the side opposite the driver.

Back and turn toward the driver's side.

Back quickly while no one is coming.

6 / 40

When should you drain air tanks that do not have an automatic tank drain?

once every 7 days

once every 14 days

at the end of each working day

every 4 hours of the working shift

7 / 40

These tires should have a minimum tread depth of 4/32 inches.

Steering axle tires

Drive axle tires

Non-steering axle tires

Donut tires

8 / 40

Select the true statement about slack adjusters:

they should move a minimum of 2 inches from the push rod attachment

they can be adjusted automatically or manually

they should only be adjusted by a mechanic that is certified in slack adjusters

they do not ever need to be adjusted

9 / 40

The air leakage rate for combination vehicles should not be more than _ psi a minute.

10 / 40

What is the normal operating range for a truck's oil pressure?

40-60 psi

This is engine-specific

30-75 psi

20-30 psi

11 / 40

Why do air brakes take longer to stop than hydraulic brakes?

it takes more time for the air to flow through the lines

longer reaction time

none of the answers listed

the lines are hotter

12 / 40

How do you know when your brakes are fading?

your speed increases when pressure is removed from the brake pedal

to control your speed on a downgrade you have to push harder on the brake pedal

the brake pedal flops to the cabin floor

to control your speed on a downgrade you have to apply less pressure to the break pedal

13 / 40

Select the statement that describes smooth bore tanks:

None of the answers listed.

They are 1 large tank.

They are divided down into smaller tanks.

They are divided with holes from liquid to flow through controlling surge.

14 / 40

You are driving a 40 foot truck at 35 MPH, how much space (in seconds) should you keep in front of you?

4 seconds

5 seconds

6 seconds

3 seconds

15 / 40

What might happen if a trailer is too high when you try to couple?

it may not correctly couple

the queen pin may fall off

all answers listed

the trailer may tip to the side

16 / 40

Select the true statement in regards to an application pressure gauge:

it is connected to the generator

it shows how much air pressure you are applying to the brakes

when accelerating it releases air

it prevents the brakes from failing

17 / 40

If your bus has an emergency exit door, it must:

Not have any signs, stickers, or markings anywhere near it.

Have a red electric door light turned on at all times.

Be closed when operating the bus.

All of these answers are correct.

18 / 40

Vehicle handling can become unsafe if the weight is not properly balanced. Hard steering can be caused by:

too little weight on the driving axles

too much weight on the steering axles

under loaded front axles

high center of gravity

19 / 40

Select the true statement about dual air brake systems:

they are required to have two warning alarms

they require less time to build up air pressure

they have a single set of air tanks and hoses

they have one set of controls for two air brake systems

20 / 40

How many seats may be placed in the aisle if the bus is a charter and is carrying agricultural (farm) workers?

21 / 40

How often should you drain your air tanks?

at the end of each week

at the end of each shift

at the beginning of each month

at the end of each trip

22 / 40

Do empty trucks have the best braking?

yes

yes, but only on wet surfaces

yes, but only if the truck is newer than 1998

23 / 40

Select the portion of the combination vehicle that is most likely to turn over suddenly when pulling a double trailer:

the front trailer

the back trailer

the tractor

all are equally likely

24 / 40

Select how you can tell if your vehicle is equipped with an anti-lock braking system:

the vehicle is manufactured after 1990

the vehicle is manufactured after 2001

the vehicle is manufactured after 2005

the vehicle is manufactured after 1998

25 / 40

What should you hook up before backing a tractor to a trailer for coupling?

the safety bar

there is nothing to be hooked up

the service and emergency air lines

the electrical service line

26 / 40

Which of the following is NOT an important reason to look far ahead when you are driving?

determine if there are any hills coming up

determine if there are any upcoming traffic lights that might require you to stop

look for brake lights from slowing vehicles

look for vehicles coming into your lane

27 / 40

What are spring brakes?

they do not function when the psi falls below 30 psi

all of these answers are correct

they are brakes that automatically come on for a truck or trailer when the psi drops too low

they are powerful springs that hold back air pressure when driving

28 / 40

Hazardous materials (that are not forbidden) carried on a bus must be:

Stored in the passenger compartment

Carried in a metal box

Labeled

All of these answers are correct

29 / 40

When inspecting the ______you are making sure that the lines and hoses are not chafed, cut, pinched, or dragged against tractor parts.

lifts/door/ties

air brake lines

mud flaps

electric/air lines

30 / 40

When approaching a school bus stop, you should:

Activate your overhead amber lights.

Continuously check all mirrors.

Gradually decrease speed until the stop.

All of these answers are correct.

31 / 40

Select the true statement in regards to driving a truck with triple or double trailers:

all answers listed

the risk of trailer jackknifes and tipping is increased compared to shorter trucks

the truck requires increased following distance compared to smaller vehicles

extra care should be taken when driving in bad weather and in the mountains

32 / 40

When stopping for railroad tracks, you must stop no closer than how many feet before the nearest track?

33 / 40

This item should be firmly attached the to frame, be solid, and clear of objects:

The lock pins

None of these answers are correct answers are correct

The catwalk

The locking jaw

34 / 40

Suspension systems:

keep the axles in place

keep the brake drums from failing

keep the load secure

keep the steering wheel tight

35 / 40

A tank vehicle:

Is a vehicle that can transport liquid.

Is a vehicle that can transport liquified gasses.

Is a vehicle that can transport bulk fertilizer.

All answers listed.

36 / 40

After deciding the type of evacuation that is necessary, the next step you must take is:

Notifying the dispatch office of the evacuation.

Dangle the radio microphone out of the driver window for later use.

Securing the bus.

Opening the emergency exits.

37 / 40

The trailer height is correct for connecting a converter dolly to a second trailer when:

the top of the kingpin lines up with the locking jaws

the trailer will slightly rise when the converter dolly is backed under it

the kingpin is resting behind the fifth wheel

the trailer will slightly lower when the converter dolly backed under it

38 / 40

To inspect the______you should pump the pedal 3 times and hold it down for 5 seconds while making sure the pedal doesn't move during those 5 seconds.

air brakes

hydraulic brakes

engine brakes

parking brakes

39 / 40

The act of operating a motor vehicle in a selfish, bold, or pushy manner, without regard for the rights or safety of others is known as.

distracted driving

road rage

defensive driving

aggressive driving

40 / 40

Is this statement true or false: You do not need to use the parking brake if are leaving your vehicle for a short amount of time.

true

only when the vehicle has over 60,000 miles on it

false

only when the vehicle has over 25,000 miles on it

Your score is

The average score is 60%

5/5 - (2 votes)

CDL Category Practice Tests

CDL Practice Test

How To Get An illinois Commercial Drivers License

Applicants can apply for their CDL and any endorsements they wish at the age of 21 years old. Those under the age of 21, but over the age of 18 are eligible to receive an in-state only CDL. Those under 21 are not eligible for driving hazmat vehicles or transporting passengers. All applicants must supply a Department of Transportation (DOT) medical certificate and pass the CDL vision test in order to be qualified to receive their CDL. All applicants are required to pass a vision test, knowledge test(s), and a practical skills assessment in order to be considered for a CDL license.

Any applicant that is described by any of the sentences below is considered disqualified from getting their CDL.

A driver that has their commercial driving privileges revoked in another state.
Any driver convicted of driving impaired in a commercial vehicle in the past 24 months.
A driver that possess more than one driver’s license.
Any driver whose license is currently denied, canceled, suspended, or revoked.

Endorsements
L – Air Brake Restriction
X – Combination
P – Passenger
C – Charter Bus
T – Doubles/Triples
H – Hazardous Materials
S – School Bus
N – Tank

Hit the Open Road

illinois CDL License Test Tips

The written exam or knowledge test is required of all CDL applicants. This exam is comprised of 50 specific questions about commercial driving. Those applying for endorsements must complete an additional knowledge test for that endorsement. These tests are between 20 and 30 questions. Those who are applying for a Class A CDL must complete an additional 20 questions about combination vehicles. All knowledge tests must be passed with a grade of 80 percent or more for an applicant to receive their CDL permit.

The Illinois CDL skills assessment must be completed by an applicant. Each assessment includes a pre-trip inspection, basic control skills, and on-road driving test. The on-road driving test includes real-life driving instances, such as low clearance bridges, downgrading for a stop, increasing gears, curves, expressways, and other instances. These are mean to ensure the applicant is fully capable of driving a commercial vehicle safely.

Additional Information

Information on the Office of the Illinois Secretary of State

The Office of the Illinois Secretary of State is responsible for the administration of the CDL requirements and testing in Illinois. To get more information contact them via:

Website: https://www.cyberdriveillinois.com/departments/drivers/drivers_license/CDL/cdl.html

Phone: 800.252.8980

Additional Illinois CDL Helpful Links

Please use the links below to access more valuable Illinois CDL testing resources and to learn more about practice driving tests for the state of Illinois.

illinois CDL Practice Test