Air Brakes #2
Air Brakes Endorsement Test | Wisconsin 2026 #2 Page 2 of 4
Train for FREE online with our Wisconsin 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 WI Class A/Class B driver license in 2026, 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 . How much distance will an air brake-equipped vehicle need to come to a complete stop if it is traveling at 55 mph under ideal driving conditions?
A vehicle's total stopping distance is made up of perception distance, reaction distance, brake lag distance, and braking distance. With all of these factors included, an air brake-equipped vehicle traveling at a speed of 55 mph under ideal driving conditions will need approximately 450 feet to come to a complete stop.
8 . To inspect slack adjusters on S-cam brakes, you need to:
Chock the wheels and disengage the parking brake.
Check each slack adjuster after parking on level ground, setting wheel chocks, and disengaging the parking brake. Pull the slack adjusters to make sure 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.
9 . Air pressure should build up in a single air system within:
In single air systems, air pressure should build from approximately 50 to 90 psi within three minutes.
10 . If the safety relief valve in the air brake system releases air:
An air brake system has a safety relief valve, which releases air from the tanks if the pressure gets too high. If the valve must operate, something in the system is wrong and should be addressed by a mechanic.
11 . What is removed when an air tank is drained?
Chlorine
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.
12 . Truck tractors with air brakes that were built on or after March 1, 1997 are equipped with:
Anti-Lock Braking Systems (ABS).
Truck tractors with air brakes that were manufactured on or after March 1, 1997 are required to be equipped with Anti-Lock Braking Systems (ABS). ABS is required in any other type of vehicle with air brakes that was manufactured on or after March 1, 1998.
2026 Wisconsin | Frequently Asked Questions
A CDL Class B license in Wisconsin allows the holder to operate single vehicles with a gross vehicle weight rating (GVWR) of 26,001 pounds or more, or any such vehicle towing another not exceeding 10,000 pounds. This typically includes buses, dump trucks, delivery trucks, and other similar vehicles. It does not cover operation of Class A vehicles.
A Class B CDL (Commercial Driver's License) in Wisconsin allows you to operate single vehicles with a gross vehicle weight rating (GVWR) of 26,001 pounds or more, or any such vehicle towing another not exceeding 10,000 pounds. This typically includes buses, dump trucks, tow trucks, delivery trucks, and straight trucks.
To acquire a Class B CDL license in Wisconsin, you must be at least 18 years old (21 for interstate driving), possess a valid Wisconsin driver's license, pass a vision test, and successfully complete a knowledge test. You'll also need to pass a skills test in the type of vehicle you plan to drive. Medical clearance may also be required.
In Wisconsin, you must be at least 18 years old to qualify for a Class B CDL license. However, to drive a commercial vehicle across state lines (interstate driving) or to transport hazardous materials, you must be at least 21 years old.
Yes, specific endorsements may be necessary for a Class B CDL license depending on the type of vehicle you plan to drive or the cargo you will carry. These can include passenger, school bus, tanker, or hazardous materials endorsements. Each endorsement requires passing additional knowledge and/or skills tests.
The Class B CDL skills assessment in Wisconsin includes three parts: the pre-trip vehicle inspection, basic vehicle control, and on-road driving. You will be tested on your ability to inspect your vehicle, control the vehicle at low and high speeds, and navigate through traffic and intersections safely.
Yes, Class B CDL license holders in Wisconsin are restricted to operating vehicles with a Gross Vehicle Weight Rating (GVWR) of more than 26,000 pounds, or towing vehicles not more than 10,000 pounds. They cannot operate Class A vehicles unless they have the appropriate endorsements. They are also subject to federal driving regulations.
Yes, in Wisconsin, the written Class B CDL test is available in English and Spanish. However, the Federal Motor Carrier Safety Administration requires that all CDL holders understand and read English well enough 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 B CDL written exam in Wisconsin if you have a disability. The Wisconsin Department of Transportation provides reasonable testing accommodations under the Americans with Disabilities Act. You'll need to provide documentation of your disability and specify the type of accommodation you need when scheduling your exam.
Yes, you can retake the Class B CDL written test in Wisconsin if you fail on your first attempt. You're allowed to retake the test the next day. However, if you fail three times, you will need to wait until your eligibility is renewed, which is typically a period of 6 months, before you can try again.