Patent ID: 8744702

Claim:
A work vehicle control device, comprising a controller configured to: control a rotation speed of an engine in correspondence to an accelerator pedal operation quantity indicating an extent to which an accelerator pedal is operated; detect a torque converter speed ratio of a speed at an input shaft and a speed at an output shaft of a torque converter, which is disposed between the engine and wheels to transmit rotation of the engine to the wheels; make a decision that a fuel efficiency deteriorating condition exists in the following situations: i) a situation in which the torque converter speed ratio is less than a predetermined value, and ii) a situation in which the torque converter speed ratio is equal to or greater than the predetermined value and a target engine rotation speed corresponding to an operation of the accelerator pedal is greater than a preset value; inform an operator within an operator's cab of results of the decision that the fuel efficiency deteriorating condition exists; set a downshift reference value that is greater than the predetermined value, for the torque converter speed ratio; and adjust a gear setting at a transmission, which is connected to the output shaft of the torque converter, to be shifted down if the torque converter speed ratio decreases to the downshift reference value.