Brake system

A brake actuator (14) includes an actuator body (38), a piston (32) held in the actuator body, and an actuator rod (16) coupled to the piston and coupelable to a brake to actuate the brake. A method of operating the brake actuator includes maintaining a first fluid pressure of a first fluid against a first side (34) of the piston to urge the piston in a brake-actuating direction, and controlling a second fluid pressure of a second fluid against a second side (36) of the piston opposite the first side of the piston to move the piston controllably in a brake-releasing direction. A brake system including the brake actuator is also disclosed.