To affect a vehicle, ABS: Question To affect a vehicle, ABS: Answers Must be on all axles. Must be on the rear axle. Can be on as few as one axle. Explanation Anti-lock brakes on only a single axle still provides a driver with more control while braking than they would have without any anti-lock brakes. This questions appears in the following tests: Iowa Air Brakes Louisiana Class A Knowledge Test Louisiana Air Brakes Mississippi Class A Knowledge Test Oregon Class B Knowledge Test
