An impact tool includes a housing, an electric motor supported in the housing, and a drive assembly for converting a continuous torque input from the motor to consecutive rotational impacts upon a workpiece capable of developing at least 1,700 ft-lbs of fastening torque. The drive assembly includes an anvil rotatable about an axis and having a head adjacent a distal end of the anvil. The head has a minimum cross-sectional width of at least 1 inch in a plane oriented transverse to the axis. The drive assembly also includes a hammer that is both rotationally and axially movable relative to the anvil for imparting the consecutive rotational impacts upon the anvil, and a spring for biasing the hammer in an axial direction toward the anvil.