A working vehicle comprising: an engine; a boom provided rotatably at one side of a vehicle body; a traveling system including a transmission; a hydraulic device system provided with a boom cylinder for rotating the boom; a distributor that distributes an output from the engine to the traveling system and the hydraulic device system; a modulation clutch contained in the traveling system and connected to the distributor; the modulation clutch being configured to perform any of engagement, disengagement, and slip between an output shaft of the engine and an input shaft of the transmission; a loading operation detection unit that detects whether a loading operation for dropping the load contained in the bucket using the boom is being performed; characterised in that the loading operation detection unit is configured to detect that the loading operation is being performed when both a first condition and a second condition are satisfied; wherein the first condition is for detecting whether the loading operation is being performed and the first condition relating to expression of operator's will; the first condition being that a boom lever is operated to raise the boom; the second condition is for preventing erroneous detection and the second condition relating to a state of the traveling system; the second condition being that a speed ratio of an input revolution speed and an output revolution speed of the modulation clutch when a brake is off is equal to or greater than a predetermined value; and the predetermined value being the maximum value, when the working vehicle is accelerated or a digging operation is performed, in a value range of the ratio of the input revolution speed and the output revolution speed of the modulation clutch; wherein the loading operation detection unit determines whether either the speed ratio, when a brake is off, is greater then the predetermined value or the brake is on; a maximum output characteristic control unit configured to select between a first engine maximum output characteristic and a second engine maximum output characteristic wherein in the first engine maximum output characteristic a maximum output torque in a predetermined engine revolution speed range is lower than that in the second engine maximum output characteristic, wherein the maximum output characteristic control unit is further configured to select the second engine maximum output characteristic, when it is detected that the loading operation is being performed; and a hydraulic oil amount control unit that decreases a clutch pressure of the clutch when it is detected that the loading operation is being performed. an engine; a boom provided rotatably at one side of a vehicle body; a traveling system including a transmission; a hydraulic device system provided with a boom cylinder for rotating the boom; a distributor that distributes an output from the engine to the traveling system and the hydraulic device system; a modulation clutch contained in the traveling system and connected to the distributor; the modulation clutch being configured to perform any of engagement, disengagement, and slip between an output shaft of the engine and an input shaft of the transmission; a loading operation detection unit that detects whether a loading operation for dropping the load contained in the bucket using the boom is being performed; characterised in that the loading operation detection unit is configured to detect that the loading operation is being performed when both a first condition and a second condition are satisfied; wherein the first condition is for detecting whether the loading operation is being performed and the first condition relating to expression of operator's will; the first condition being that a boom lever is operated to raise the boom; the second condition is for preventing erroneous detection and the second condition relating to a state of the traveling system; the second condition being that a speed ratio of an input revolution speed and an output revolution speed of the modulation clutch when a brake is off is equal to or greater than a predetermined value; and the predetermined value being the maximum value, when the working vehicle is accelerated or a digging operation is performed, in a value range of the ratio of the input revolution speed and the output revolution speed of the modulation clutch; wherein the loading operation detection unit determines whether either the speed ratio, when a brake is off, is greater then the predetermined value or the brake is on; a maximum output characteristic control unit configured to select between a first engine maximum output characteristic and a second engine maximum output characteristic wherein in the first engine maximum output characteristic a maximum output torque in a predetermined engine revolution speed range is lower than that in the second engine maximum output characteristic, wherein the maximum output characteristic control unit is further configured to select the second engine maximum output characteristic, when it is detected that the loading operation is being performed; and a hydraulic oil amount control unit that decreases a clutch pressure of the clutch when it is detected that the loading operation is being performed.