iowa
CDL Practice Test

Below are practice questions for the Iowa CDL test. The site is free and you are able to take the practice test as many times as you need to as you prepare to obtain your Iowa CDL. The questions and answers covered in these Iowa practice CDL tests are taken from the Iowa DOT CDL manual. 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

Select the definition of "off-tracking."

it is when the rear wheels of the vehicle follow a different path way than that of the front wheels

it is when the trailer wheels go in a different direction from the front wheels

none of the answers listed

it is wheen the rear wheel skid and the front wheels maintain a straight path

2 / 40

Which of the following materials would be an acceptable floor liner for moving Division 1.1 or 1.2 materials?

Non-ferrous metal

Stainless steel

Carbon steel

All of these answers are correct

3 / 40

To maintain alertness during the trip, drivers should:

get 8-9 hours of sleep

avoid medications that cause drowsiness

all of these answers are correct

schedule trips during the daytime hours

4 / 40

Bus drivers must have a commercial driver license if they drive a vehicle designed to seat more than:

16 or more persons, including the driver.

15 or more persons, including the driver.

20 or more persons, excluding the driver.

10 or more persons, including the driver.

5 / 40

Within 3 minutes, this gauge pressure should build to 90 psi from 50 psi.

Voltmeter gauge

Air pressure gauge

Oil pressure gauge

Coolant pressure gauge

6 / 40

At what pressure is the safety valve in the air compressor tank set to open?

100 psi

125 psi

150 psi

225 psi

7 / 40

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

the center of the kingpin is past the locking jaw

all answers listed

the kingpin is over the fifth wheel

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

8 / 40

Carry-on baggage cannot be stored:

On the seats.

Behind the seats.

Under the seat.

In the aisles and stairwells.

9 / 40

The trailer should be lowered so that _____.

the tractor comes in contact with the nose of the trailer

you are able to use the landing gear to make adjustments

it is slightly raised when the tractor is backed under it

the trailer is high above the fifth wheel

10 / 40

Should your air compressor stop working:

there will still be air pressure left in the air tanks

you will lose your ability to brake immediately

the brakes will lock up on you immediately

there will be no affect to your brakes

11 / 40

Select the true statement:

you should always ride the brakes

wait to brake heavy vehicles for as long as you can

a bobtail tractor will take longer to stop than a combination vehicle that is loaded to the max

light vehicles require more braking power than heavier vehicles

12 / 40

Which of the following is a recommended procedure when unloading the students?

Put the transmission in neutral gear and put on the brakes.

Tell students to remain seated until they are told to exit.

Let the students begin moving to the front of the bus before it's fully stopped to maximize efficiency.

Position yourself outside of the bus in front of crossover mirror to supervise unloading.

13 / 40

How do you test your service brakes?

apply pressure to the brake pedal when moving at highway speeds

pull over and activate the parking brake

release the air pressure and activate the parking brake

after releasing the parking brake, move forward slowly and apply pressure to the brake pedal

14 / 40

Before transporting a sealed load, you must check:

a picture of whatever is inside

that you don't exceed gross weight and axle weight limits

all of these answers are correct

a small sample of whatever is inside

15 / 40

This carries hydraulic fluid or air to the wheel brake assemby.

Slack pieces

Brake lines/hoses

Brake drums

Connector rods

16 / 40

When transporting hazardous waste, you must:

Carry a uniform hazardous waste manifest in the truck.

Have the word "waste" before the name of the material on the bills.

All of these answers are correct.

Sign a uniform hazardous waste manifest.

17 / 40

What is the best way to prevent brakes form overheating while drive down a steep grade?

use countersteering practices

use the trailer brakes only

use the stab braking method

drive at a speed of 5 mph below your safe speed

18 / 40

Which of the following is a reason to evacuate the school bus?

The bus abs warning light is on.

A child set off a stink bomb inside the bus.

The bus is stalled on a shoulder of a 4-lane divided highway and it is getting hot inside.

The bus is stalled on a rail road track, but there is no train in sight.

19 / 40

When using turn signals, which of the following should be avoided?

signal when you are merging into traffic

signal just before you start to make a turn

signal when you want to change lanes

signal before you exit

20 / 40

Signs of distracted drivers include:

vehicles exiting the roadway

individuals driving at a consistent speed above the speed limit

individuals listening to music too loudly

drivers having conversations with passengers

21 / 40

Which of the following statements about loading and unloading cargo tanks is false?

The person in attendance must be aware of the danger.

The person attending the tanker must have a clear view of it.

The person in attendance must be within 50 ft of the tanker.

The person in attendance must be authorized and able to move the vehicle.

22 / 40

Select the inappropriate way to test for the low pressure warning signal.

decreased the air pressure by stepping on and off the brake pedal

ask for a pedestrian to listen for the signal

have the electrical power on

turn off the engine

23 / 40

Which of the following should you do when driving the school bus in high wind?

Drive only head-in to the wind to avoid cross-wind buffeting.

Speed up to get away from the wind as quickly as possible.

Pull off the road to wait for the winds to die down.

Keep a strong grip on the steering wheel and try to anticipate gust.

24 / 40

Of the following hazardous material classes, which is the most dangerous?

Division 62

Division 61

Division 64

Division 63

25 / 40

The most important hand signal you should agree on with a helper is:

“stop”

“go”

“turn up the music”

“faster”

26 / 40

How should the trailer be lined up when preparing to back the tractor up?

directly in front of the trailer

about 12 degrees to the left

directly behind the trailer

about 12 degrees to the right

27 / 40

Select the true statement in regards to brake drums or discs:

they are not allowed to have any cracks

the linings should fit loosely around the brake shoe

they should always be kept well-greased up

they should not have cracks that are longer than half the width of the friction area

28 / 40

This component should be checked that it is solid, securely bolted to the tracture frame, and clear of objects.

The catwalk

The fifth wheel

The locking kingpin

The platform

29 / 40

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

30 / 40

This object should not be spliced, cut, chafed, or worn through to allow steel braid to show.

The lockjaw

Tires

Electric/air lines

Mud flaps

31 / 40

Why should you test the tractor protection valve?

to avoid loss of air from the air hose

to avoid loss of air from the trailer brakes

to avoid the emergency brakes kicking on due to loss of air

all answers listed

32 / 40

Some city transit buses may have a brake-door interlock system, this system:

Releases the brakes.

Should be used in emergencies.

Works when the rear door is open.

Should be used in place of the parking brake.

33 / 40

You must be alert for road hazards so that:

Accident reports will be accurate.

You can help impaired drivers.

Law enforcement personnel can be called.

You will have time to plan your escape if the hazard becomes an emergency.

34 / 40

What are shippers trying to accomplish when they package the material?

Make it as light as possible.

Make it easy to open and close.

All of these answers are correct.

Make it easy to identify.

35 / 40

When transporting explosives you may not park:

Within 300 feet of a tunnel.

Within 5 feet of the traveled part of the road.

All of these answers are correct.

Near an open fire.

36 / 40

What is most likely to occur when driving a tanker truck and the front wheels begin to skid?

Nothing will occur.

The surge will disconnect the tank from the truck.

No matter how you steer, you will continue in a straight line.

The tank will roll over.

37 / 40

This object is required to be checked for damage, that it's secure, and strong enough to handle any cargo.

The apron

The fifth wheel

The header board

The platform

38 / 40

When conducting a pre-trip inspection, the most important item to verify is _____.

that the registration is in the cup holder

that the radio transmits a signal

that the tire tread is sufficient for the expected driving conditions

that there are no leaks in the air brake system

39 / 40

This item should not be rusted, bent, or damaged and centered over evenly spaced tires and dual wheels.

Frame

Fifth wheel

Lug bolts

Spacers

40 / 40

Alcohol evaporators in some air brake systems help to:

decrease the chances of ice in the air brake valves in cold weather

cleans out oil from the air lines

it removes fuel from the air lines

decreases the risk of water in the air brake valves in cold weather

Your score is

The average score is 0%

5/5 - (1 vote)

CDL Category Practice Tests

CDL Practice Test

How To Get An iowa Commercial Drivers License

Individuals may apply for their CDL starting at age 18. To be eligible for interstate driving as well as HazMat and Doubles/Triples applicants must be 21 years of age or older. All individuals applying for an Iown CDL must present a Medical Examiner’s Certificate according to the United States Federal Regulations.

If any one of the descriptions below is true about an applicant, they will be disqualified from receiving their CDL.

Driver posses more than one driver’s license.
Driver was convicted of driving under the influence in the past 24 months.
Driver has a suspended, denied, canceled, or revoked driver’s license.

Endorsements
H – Hazardous Materials
N – Tank Vehicle
T – Doubles/Triples
X – Hazmat and Tank Comb
P – Passenger Vehicle
S – School Bus

Drivers must take a knowledge test as well as a practical skills test to showcase their knowledge of commercial driving laws and their ability to operate a commercial vehicle.

Hit the Open Road

iowa CDL License Test Tips

Applicants must complete a general knowledge test to display their understanding of commercial driving laws. The general knowledge exam is comprised of 50 questions. Those seeking a Class A CDL will need to complete an additional 20 question test on combination vehicles. Applicants seeking additional endorsements will need to take an additional test on the endorsement topic. The Passenger, Tank, and Doubles/Triples Endorsements are 20 question tests. Removing the Air Brake Restriction, the Iowa Operator and School Bus Endorsements are 25 questions. The Hazmat Endorsement is a 30 question test. All applicants must pass the respective assessments with a score of 80 percent or better to receive their Iowa CDL permit.

A skills assessment is required of all applicants. This assessment is comprised of three parts, which are the pre-trip inspection, basic controls skills, and on-road driving. Individuals applying for their P and S endorsements will be required to take the skills test in the respective vehicle for their endorsement.

Additional Information

Information on the Iowa Department of Transportation

The Iowa Department of Transportation administers CDL requirements and testing in Iowa. To get more information contact them via:

Website: https://iowadot.gov/DriversVehicles#CommercialDrivers

Phone: 515.239.1101

Additional Iowa CDL Helpful Links

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

iowa CDL Practice Test

CDL Category Practice Tests

CDL Practice Test

How To Get An iowa Commercial Drivers License

Hit the Open Road

iowa CDL License Test Tips

Additional Information

Information on the Iowa Department of Transportation

Additional Iowa CDL Helpful Links

iowa
CDL Practice Test