Air Brakes #2
Air Brakes Endorsement Test | Wisconsin 2025 #2 Page 3 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 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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13 . Which of the following is not a part of an air brake system?
An axle brake system
Air brakes consists of three separate braking systems: the service brake system, the parking brake system, and the emergency brake system.
14 . A tank endorsement is:
Optional when transporting hazardous materials.
In general, a tank endorsement is required to a drive tank vehicle used to transport liquids or gases. This applies to both hazardous and non-hazardous materials.
15 . Why do you need to drain air tanks regularly?
To remove bad air from the tanks
Compressed air in an air brake system usually contains a certain amount of water and compressor oil. The water and oil can damage the brakes if left to accumulate in the system. Tanks must be drained regularly to remove this build-up.
16 . If using air tanks with manually operated drains, how often should you drain the tanks?
Once every 3,000 miles
To prevent the build up of oil and water in a vehicle's air tanks, manually operated air tank drains should be used at the end of each day of driving.
17 . A low air pressure warning signal should activate:
When tank pressure falls below 5 psi.
In an air brake system, a low air pressure warning signal must come on if air pressure in the tanks falls below 60 psi. This warning signal may come in the form of a light, a buzzer, or a wig wag.
18 . If braking at a speed of 55 mph while driving on dry pavement, the brake lag can add ____ to your vehicle's total stopping distance.
10 feet