Question Failing to drain air tanks could result in: Answers Water accumulations freezing and causing brake failure. Squishy brakes. Too much air collecting in the tanks. Explanation In an air brake system, the air tanks must be periodically drained to remove accumulations of water and compressor oil. If water is not removed, it could freeze in cold weather and cause brake failure. Take a FREE Practice Test Now This questions appears in the following tests: Missouri Knowledge Test Class A , Oklahoma Knowledge Test Class A , Arkansas Knowledge Test Class B , Ohio Double , Delaware Air Brakes , Kentucky Air Brakes , Mississippi Air Brakes , Montana Air Brakes , Utah Air Brakes ,