Question Why do large vehicles use air brakes? Answers Other brake systems squeak too loudly. Air brakes are very effective systems. Other braking systems are hard to come by. Explanation If used and maintained properly, air brakes are a safe and effective way to stop large, heavy vehicles. Take a FREE Practice Test Now This questions appears in the following tests: Vermont Knowledge Test Class B , North Carolina Double , Louisiana Passenger , Hawaii Air Brakes , Idaho Air Brakes , Missouri Air Brakes , New Hampshire Air Brakes , Ohio Air Brakes , Virginia Air Brakes , Washington Air Brakes ,