PROBLEM TO BE SOLVED: To simplify a configuration, improve operation ability and perform draft control in which sensitivity can be adjusted.SOLUTION: A tractor performs position control by actions of a first link mechanism 19 for linking a spool 17A of a control valve 17 to a height setting lever 18 and a feedback link mechanism 20 for linking the spool 17A to a lift arm 15, and performs draft control by action of a second link mechanism 22 for linking the spool 17A to a load detection member 21 and the feedback link mechanism 20. A sensitivity adjustment mechanism 23 links to an operation of a sensitivity adjustment lever 44 provided on an operation part, changes a position of an oscillation fulcrum shaft 42 of a relay arm 41 provided on the second link mechanism 22, and changes a gap S between an oscillation arm 30 of the first link mechanism 19 and an operation arm 39 of the second link mechanism 22, for adjusting operation sensitivity of the spool 17A in the draft control.SELECTED DRAWING: Figure 2
