WORK VEHICLE, AND WORK VEHICLE CONTROL DEVICE AND CONTROL METHOD

A braking force function determination unit determines at least one of an offset and an inclination for a required braking force in a braking force function which indicates a relationship between a rotational speed of an output shaft of a transmission and the required braking force and in which the required braking force monotonically increases with respect to the rotational speed such that the smaller a stage number of a selected speed stage which is input into a traction force instruction device, the larger an absolute value of at least one of the offset and the inclination. A required braking force function determination unit determines the required braking force based on the rotational speed of the output shaft of the transmission and the braking force function.