A fluid-driven linear motor comprises a cylinder (5), a piston (4) and a piston rod (3) connected to the piston (4), wherein the two sides of the piston (4) in the cylinder (5) are alternatively supplied with fluid from a slide valve arrangement, the slide valve arrangement including a slide (9) accommodated in a chamber and which is shifted between its end positions controlled by a pilot rod (22) coaxially mounted in a through bore (12) in the slide (9). The pilot rod (22) is adapted to alternately set the through bore (12) in fluid connection with the ends of the slide (9) when the piston (4) is located in its end positions. The pilot rod (22.) is provided with an extension rod (204) adapted to slide inside a bore (203) inside said piston (5) and said piston rod (3), so that the stroke length of the linear motor can be extended. Moreover, a pressure chamber (209) is provided at the distal end of the pilot rod (22), said pressure chamber (209) being adapted to hold on the pilot rod (22) with a holding force when in its end positions until mechanical forces from the piston overcome said holding force.