Air Brakes #1
Air Brakes Endorsement Test | Iowa 2025 #1 Page 2 of 4
Train for FREE online with our Iowa CDL air brake test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a IA Class A/Class B driver license in 2025, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that the requirements for CDL may vary from state to state.
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7 . A slack adjuster should move no more than ____ from where it is attached to the push rod.
Before a trip, you should check each slack adjuster after parking, setting wheel chocks, and disengaging the parking brake. Pull the slack adjusters to make sure that they do not move more than about one inch from where the push rod is attached. If they move more than one inch, they may be out of adjustment and will need to be fixed.
8 . Once the air tanks are at an air pressure level of 125 psi, the air compressor governor will:
An air compressor governor will stop the compressor from pumping air once the air tanks are at an air pressure level around 125 psi. This air pressure level is referred to as the "cut-out" level.
9 . Brakes can get out of adjustment quickly, especially:
Brakes are particularly prone to getting out of adjustment if they are hot. Be sure to routinely check the adjustment of your brakes. For a vehicle to be safely controlled, all brakes must be properly functioning and adjusted.
10 . Air tank drains should:
In an air brake system, air tank drains are used to remove water and compressor oil from the air tanks. When operating a drain, be sure to drain the tank completely.
11 . While driving, ____ generally holds spring brakes in place.
While driving, spring brakes are generally held in place by air pressure. If the air pressure gets low enough, the springs will activate the brakes.
12 . An alcohol evaporator is especially important:
Some air brake systems contain an alcohol evaporator. This evaporator introduces alcohol into the system to help prevent ice from forming in cold weather.
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2025 Iowa | Frequently Asked Questions
A CDL Class A license in Iowa is defined as a commercial driver's license that permits the holder to operate any combination of vehicles with a Gross Vehicle Weight Rating (GVWR) of 26,001 pounds or more, provided the GVWR of the vehicle(s) being towed is in excess of 10,000 pounds. This includes tractor-trailers, truck and trailer combinations.
A Class A CDL license in Iowa allows the holder to operate various types of vehicles including tractor-trailers, truck and trailer combinations, tank vehicles, livestock carriers, and flatbeds. The license covers vehicles with a Gross Vehicle Weight Rating (GVWR) over 26,001 pounds and the towed vehicle is more than 10,000 pounds.
To obtain a Class A CDL license in Iowa, you must be at least 18 years old (21 for interstate driving), possess a valid non-commercial driver's license, and pass a vision test. You'll also need to pass written knowledge tests, a skills test, and a pre-trip vehicle inspection. For certain endorsements like hazardous materials, a background check is required.
In Iowa, you must be at least 18 years old to qualify for a Class A CDL license. However, please note that while you can obtain a CDL at 18, federal law requires drivers to be at least 21 years old to drive commercial vehicles across state lines or to transport hazardous materials.
Specific endorsements aren't required for a Class A CDL license in Iowa but they can enhance your license. Endorsements like "T" for double/triple trailers, "P" for passenger vehicles, or "H" for hazardous materials allow you to operate specific types of vehicles or carry certain types of cargo. Each endorsement requires passing additional tests.
The Class A CDL skills test in Iowa encompasses three main areas: pre-trip inspection, basic vehicle control, and on-road driving. The pre-trip inspection tests your ability to inspect your vehicle before driving. Basic vehicle control assesses your ability to control the vehicle. On-road driving tests your ability to drive the vehicle in various traffic situations, including turns, intersections, and highway driving.
Yes, Class A CDL license holders in Iowa may face limitations based on their medical qualifications, the type of vehicle they're allowed to operate, and the cargo they can transport. This could result in restrictions such as "No passengers", "Intrastate only", or "No air brake equipped". Also, drivers under 21 are limited to intrastate operation only.
In Iowa, the written Class A CDL test is primarily administered in English. However, some locations may offer the test in Spanish. It's important to note that even if the test is taken in Spanish, the Federal Motor Carrier Safety Administration requires all commercial drivers to read and speak English sufficiently to converse with the general public, understand highway traffic signs and signals, respond to official inquiries, and make entries on reports and records.
Yes, you can request accommodations for the Class A CDL written test in Iowa if you have a disability. The Iowa Department of Transportation is committed to providing reasonable accommodations in accordance with the Americans with Disabilities Act. You should contact your local DOT office in advance to discuss your needs and arrange for modifications or aids to assist you during the test.
Yes, if you don't pass the Class A CDL written test in Iowa, you can retake it. However, you must wait at least one day before retaking the test. Please note that there may be additional fees for each retest. It's advised to review your study materials thoroughly before attempting the test again to increase your chances of passing.
