Air Brakes #1
Air Brakes Endorsement Test | South Dakota 2025 #1 Page 4 of 4
Train for FREE online with our South Dakota 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 SD 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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19 . The air compressor governor controls:
The speed of the vehicle.
In an air brake system, the air compressor governor controls when the air compressor pumps air into the air storage tanks.
20 . Both systems in a dual air brake systems share:
An air compressor.
Both systems in a dual air brake system share a single air compressor. If the air compressor is damaged, neither system will be able to operate properly.
21 . The parking brake should be:
Used to stop the vehicle in normal driving.
The parking brake should be applied every time you park your vehicle.
22 . What kind of force must emergency brakes use?
Electrical
Because air pressure can eventually leak away, the emergency brakes in an air brake system must be held on by mechanical force.
23 . Vehicles with dual air brake systems:
Do not need time to build air pressure before a trip.
Before driving a vehicle with a dual air brake system, you must allow the air compressor time to build up at least 100 psi of air pressure in both the primary and secondary systems.
24 . Air tank drains:
Must remain open while driving.
In an air brake system, the air storage tanks are equipped with drains to allow water and compressor oil to be removed. The water and oil can damage the brakes if left to accumulate in the system.
25 . An air compressor governor will stop the compressor from pumping air once the air tanks have an air pressure level of:
80 psi.
An air compressor governor will stop the compressor from pumping air once the air tanks are at an air pressure level of 125 psi. This air pressure level is referred to as the "cut-out" level.
2025 South Dakota | Frequently Asked Questions
A CDL Class A license in South Dakota 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 exceeds 10,000 pounds. It's typically used for semi-trucks and tractor-trailers.
In South Dakota, a Class A CDL license allows you to operate a range of commercial vehicles. These include tractor-trailers, truck and trailer combinations, flatbeds, livestock carriers, and tank vehicles. It also allows the operation of all vehicles under Classes B and C, provided you have the appropriate endorsements.
To obtain a Class A CDL license in South Dakota, applicants must be at least 18 years old (21 for interstate driving), possess a valid South Dakota driver's license, pass a vision test, and successfully complete a knowledge test and skills test. They must also submit a Medical Examiner's Certificate and pass a background check if hauling hazardous materials.
In South Dakota, to qualify for a Class A CDL license, you must be at least 21 years old for interstate driving. However, if you plan to drive only within South Dakota (intrastate driving), you can apply for a Class A CDL license at 18 years old.
While a Class A CDL license in South Dakota allows you to operate a variety of vehicles, specific endorsements may be required for certain types. For example, a tanker endorsement is needed to haul liquid loads, a hazmat endorsement is required for transporting hazardous materials, and a doubles/triples endorsement is necessary for towing double or triple trailers.
The Class A CDL skills test in South Dakota encompasses three parts: a pre-trip inspection to ensure the vehicle is safe to drive, a basic controls test to assess your ability to control the vehicle, and a road test to evaluate your on-road driving skills under various traffic conditions and maneuvers. It's important to pass all three parts.
Yes, there are limitations. Class A CDL license holders in South Dakota are restricted by the federal hours of service regulations, which limit driving time to prevent fatigue. Additionally, they must comply with weight limits and may need specific endorsements for certain types of vehicles or cargo. Also, CDL holders are held to stricter DUI standards compared to regular drivers.
Yes, it is possible. In South Dakota, the written Class A CDL test is available in multiple languages, including Spanish. However, the Federal Motor Carrier Safety Administration requires all commercial drivers to read and speak English sufficiently to converse with the general public, understand 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 if you have a disability. South Dakota's Department of Public Safety complies with the Americans with Disabilities Act (ADA), providing reasonable accommodations such as accessible testing locations, additional time, or alternative test formats. However, you must provide appropriate documentation of your disability when making your request.
Yes, if you don't pass the Class A CDL written test in South Dakota, you can retake it. However, you must wait at least one day before retesting. There may be additional retest fees, and if you fail the test multiple times, additional restrictions or requirements may be imposed. Always review the manual and consider a prep course before retesting.