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

When inspecting your bus, you must make sure that:

Emergency exit handles are secure.

Every handhold and railing is secure.

All of these answers are correct.

Rider signaling devices are working.

2 / 40

The blind spot behind the bus could extend to how many feet?

200 feet

300 feet

100 feet

400 feet

3 / 40

Secure baggage and freight in ways that avoid damage and:

Allow the driver to move freely and easily.

Protect riders from injury if carry-ons fall or shift.

Allow riders to exit by any window or door in an emergency.

All of these answers are correct.

4 / 40

Select the action that is not recommended when driving on slippery roads:

keep other drivers out of your side space

none of the answers listed

use a light pressure with the the brake and accelerator pedals

use a speed retarder or engine brake

5 / 40

The average person requires how many hours of sleep per 24 hour period?

6 or 7

5 or 6

7 or 8

8 or 9

6 / 40

If you are traveling at 55 mph in a 30-foot vehicle, you should leave how many seconds of following distance?

4 seconds

6 seconds

7 seconds

3 seconds

7 / 40

How do you check the coolant level?

Remove the radiator cap once it is at operating temperature.

While wearing rubber gloves and safety glasses.

Inspect the reservoir sight glass or remove the radiator cap if the engine isn't hot.

None of the answers listed.

8 / 40

What color are all school buses painted?

National school bus yellow.

The individual district decides the exact color.

Orange yellow.

Florescent yellow.

9 / 40

Select when you should use the parking brake:

when you are leaving your vehicle for more than an hour

with rare exception, every time you leave your vehicle

each time you leave your vehicle for any amount of time

when in residential areas

10 / 40

Which of the following statements about downshifting is NOT true?

downshift when you get to the bottom of a hill

downshift before climbing a hill

downshift before starting down a hill

downshift before entering a curve

11 / 40

Which of the following statements about the bus interior is false?

Never drive with an open emergency exit door or window.

The seats must be safe for riders all seats must be securely fastened to the bus.

If you use your outside lights, you don't need to turn on red emergency door light.

If there is a red emergency door light, it must work.

12 / 40

How can you check slack adjusters?

it is not possible to check manually

by using a fixed wrench

by pulling hard on each slack adjuster

by frequently checking the pressure gauge

13 / 40

Select the true statement about speed and stopping distance.

When the road is wet it will double your stopping distance.

You need two times the stopping distance when driving at 40 mph compared to 20 mph.

None of these answers are correct.

Tank surge will decrease your stopping distance.

14 / 40

You should_____when an emergency requires you to quickly stop your tanker.

use the emergency brakes only

turn off the abs and brace for impact

keep a firm pressure on the brake pedal

use stab or controlled braking

15 / 40

Front wheel brakes are good under what kind of conditions?

any weather conditons

ideal weather conditions

they are not ideal

icy or wet conditions

16 / 40

At around____the governor allows the air compressor to start pumping again:

125 psi

175 psi

225 psi

100 psi

17 / 40

You do not have to stop at railroad crossings, but must slow down and carefully check for other vehicles:

Where a policeman or flagman is directing traffic.

At crossings marked as "exempt" or "abandoned".

All of these answers are correct.

If a traffic signal is green.

18 / 40

When inspecting the_____you pump the pedals 3 times and then hold it down for 5 seconds feeling for no movement to occur.

engine brakes

hydraulic brakes

all answers listed

emergency brakes

19 / 40

Select the false statement about suspension:

Check for distorted or broken coil springs.

Check for shifted, missing, or cracked leaf springs.

Check to make sure torsion bars and/or arms are lubricated.

Check for broken or cracked spring hangers.

20 / 40

It takes special care to drive tankers with liquid in them because:

The movement of the liquid even when the truck is stopped.

The high center of gravity of the load.

The baffles create odd rocking motions.

The low center of gravity of the load.

21 / 40

When driving in very hot temperatures, you should:

let your tires cool down (remain stopped) if they are too hot to touch

check your tires every 2 hours or every 100 miles

all of these answers are correct

insure that you have enough antifreeze in the system

22 / 40

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

“turn up the music”

“go”

“stop”

“faster”

23 / 40

If you are hauling hazardous materials and have ___ tires on your vehicle, you must stop and check them every time you park.

bias

radial

treaded

dual

24 / 40

The 3 parts of the air brake system are: service brakes, parking brakes, and ____.

v-cam brakes

bolt brakes

disc brakes

foot brakes

25 / 40

What is the brake system that applies and releases the brakes when the brake pedal is used?

lock brake system

service brake system

none of the answers listed

engine brake system

26 / 40

The minimum tread depth for tires other than the front tires is ____.

1/32

2/32

4/32

3/32

27 / 40

What are the three hazard classes should NOT be loaded into a trailer that has a heater air conditioner unit?

Class 1 explosives, class 8 corrosives, and division 5 oxidizers.

Class 2 explosives, class 3 flammable solids, and division 21 inhalation hazard.

Class 1 explosives, class 3 flammable liquids, and division 21 flammable gas.

None of these answers are correct.

28 / 40

Liquid surge affects the handling of a tanker by:

Moving the truck in the direction of liquid flow.

Allowing you to stop faster.

Allowing you to take tighter turns.

Decreasing the wind drag.

29 / 40

Select how you would check the truck's slack adjusters.

listen for any strange noises while applying pressure to the brake pedal

all of these answers are correct

while wearing gloves, pull hard on each slack adjuster that you can reach

brake hard after accelerating

30 / 40

An air system that is fully charged will typically have ___ psi of pressure.

200

250

125

31 / 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

false

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

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

32 / 40

Which of the following must drivers have in their possession while transporting class A or B explosives?

A gas mask.

The carrier's insurance policy.

The written route plan.

None of these answers are correct.

33 / 40

What is a technical name?

The medical term for hazardous materials used by medical personnel.

The name for a hazardous material most commonly used on the street.

The name for a hazardous material used in scientific journals and texts, recognized as its chemical and microbiological name.

The name for a hazardous material most commonly used in the trucking community, accepted as standard.

34 / 40

Which of these statements about signaling is correct?

Leave your signal on long after you've changed lanes.

Signal to others that it is safe to pass your bus.

Signal your intentions early and continuously.

Signaling is a warning, not a request.

35 / 40

Select the statement that best describes what the service line is for.

it is controlled by the foot brake and carries air

all answers listed

it is controlled by the trailer hand brake and carries air

it is controlled by the foot brake or trailer hand brake and carries air

36 / 40

What is a passive railway crossing?

The type of crossing with no cross buck sign.

The type of crossing, which does not have any type of traffic control device.

The type of crossing where you can pass the tracks without stopping.

The type of crossing on which the driver does not have to stop.

37 / 40

All standing riders must stay:

In front of the standee line.

Behind the standee line.

Forward of the rear of the driver's seat.

Within two feet of an emergency exit.

38 / 40

An "A/W" the first column of the hazardous materials table means:

There is no restrictions with this material if shipped by water only.

This material has no restrictions when shipped by air and/or water.

It is ok to ship this material by air only.

This material is only restricted when shipped by air and/or water.

39 / 40

In what position should the converter dolly air tank drain valve be in for double trailer combination?

in an open position

in a 1/3 open position

in a halfway closed position

in a closed position

40 / 40

A driver of a tanker should use an escape ramp when _____.

only when it's raining

the vehicle has lost braking power

only in ideal conditions

when the tanks has bulkheads

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