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Drivers who want to drive combination vehicles must pass the combination vehicles test. The Iowa CDL combination test consists of 20 questions, and you'll need at least 16 correct answers to pass (80%). The test covers the combination vehicles section of the Iowa CDL Manual. Take this practice test now to prepare for the actual IA CDL combination test!
1.
An item that is 15 feet long placed on a flatbed trailer should have at least:
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2 tie-downs.
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3 tie-downs.
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1 tie-down.
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2.
Having ABS on only the trailer:
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still gives you more control over your vehicle during braking.
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makes the trailer more likely to swing out.
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is very dangerous.
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3.
Air brakes:
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are an effective way to stop large and heavy vehicles.
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should be used only when driving on wet roads.
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are prohibited on larger vehicles.
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4.
In combination vehicles with air brakes, the trailer air supply control should pop out when the air pressure falls within the range of:
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100 to 120 psi
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10 to 20 psi
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20 to 45 psi
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5.
In combination vehicles with air brakes, the trailer air supply control:
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is used to control the tractor protection valve.
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is a coupling devices used to connect the service and emergency air-lines from the tractor to the trailer.
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is used to keep the trailer behind the tractor.
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6.
Anti-lock brakes:
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increase your stopping distance.
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help you stop faster.
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keep your brakes from locking up when you brake hard.
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7.
When driving on slippery roads, you should NOT:
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use the engine brake.
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go slowly.
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try to anticipate stops early.
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8.
A trailer jackknife is more likely to happen when the trailer is:
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empty.
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overloaded.
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loaded to its full capacity.
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9.
If you will be transporting hazardous materials that require placards, you must:
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transport the materials at night only.
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obtain a hazardous materials endorsement.
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obtain a special transit permit.
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10.
Overloading can have negative effects on:
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steering.
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braking.
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All of the above.
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Frequently Asked Questions
If you are under 18, you must follow the Iowa Graduated Driver Licensing (GDL) Program. Here are the three phases of the program and the corresponding ages:
- Instruction permit? you must be 14 years old. After holding the permit for six months without traffic violation, you can also apply for a minor school license at 14 ½ years old. This special permit is optional and allows you to drive to school or to school activities within a 50-mile distance from your home.
- Intermediate license ? you must be 16 years old and have held an instruction permit for 12 months.
- Full license ? you must be at least 17 and have held an intermediate license for 12 months. Alternatively, you can directly obtain a class C driver's license at 18.
You have two options:
- You can schedule an appointment to take the exam at a service center. Simply locate the nearest Iowa DMV branch and choose your preferred date and time.
- If you are a minor between 14 and 17, you can take the knowledge test at a participating school/agency or at home using an electronic device connected to the internet. Once your parent completes and submits the application to Proctor Knowledge Exam Form, you’ll receive an email with instructions for proceeding. After successfully passing the exam, make an appointment to obtain the permit.
You can schedule an appointment for either option on the Iowa Department of Transportation website.
When applying for a driver’s license for the first time, you must bring the following documents:
- Proof of identity, date of birth, and lawful status (e.g, U.S. passport, birth certificate, certificate of naturalization). If your legal name differs from your identity document, provide proof of the change, such as a certified marriage certificate, court order documents, or ID card.
- Proof of Social Security Number (SSN).
- Two proofs of Iowa residency and current residential address (e.g, Iowa voter registration card, utility bill, credit card statement…). If you are under 18 and unmarried, your parent/guardian must sign the Written Consent form to establish your residence. Additionally, provide a second printed document displaying your current name and current Iowa residential address, such as a report card or medical form.
You can use the online checklist provided by the Iowa DOT to ensure you have all the required documents.
The DMV written test in Iowa is not exclusively provided in English but is offered in various languages, including Albanian, Arabic, Bosnian, Burmese, Cambodian, Chinese, French, German, Greek, Hebrew, Hmong, Italian, Korean, Laotian, Polish, Portuguese, Russian, Somali, Spanish, and Vietnamese. If you need an interpreter for a language not provided, you have to schedule an appointment.
To get ready for the DMV written test, start by reading the Iowa Driver License Manual. This manual has all the info you need to study for the exam: traffic signs, road rules, and safe driving practices. Then, check what you've learned with our free practice tests!
For new drivers in Iowa, various restrictions apply:
Instruction Permit
- You cannot drive alone and you must be accompanied by a driver education instructor, a licensed parent/guardian, a licensed member of your family who is at least 21, or a licensed adult who is at least 25 (with parental permission if you are a minor).
Minor School License
- You can't drive alone, except for school activities between 5 a.m. and 10 p.m.
Intermediate License
- You cannot drive alone between 12:30 a.m. and 5 a.m., unless a parent/guardian completes a Waiver of Intermediate Driver’s License Hour Restriction form.
- For the first six months, you cannot transport more than one minor without supervision, except for siblings.
The instruction permit is valid for four years. During this period, complete the 20 hours of supervised driving and after holding the permit for 12 months and maintaining a clean driving record for 6 months, you can apply for the intermediate license.
If you fail your DMV written test in Iowa, you have to wait at least one business day before retaking it. Before trying again, focus on the sections of the manual you have overlooked and consider signing up for DMV Premium to access additional practice tests!