A self directed pool cleaning vehicle comprising a body carrying water inlet and outlet ports with the inlet port being located on the bottom of the body with the body containing a filter is described. A drive mechanism propels the vehicle in two generally opposed directions. Two axles which each carry two wheels support the body and control its direction of movement. One axle is mounted to the body via slots that extend in the directions of motion such that this axle can move toward either end of the slots. A steering structure is provided with a portion that moves to close a portion of one of the slots and can be locked in a position that prevents one end of an axle from traversing its slot. Thus when this axle is the trialing axle it is held at other than a right angle to the two generally opposed directions.