An idler assembly for a track roller frame includes a housing element having a central cavity, the housing element being connectable to an end of the track roller frame. A yoke element is movably disposed in central cavity and has spaced apart first and second arms, the yoke element is connectable to a longitudinally extending piston in the track roller frame. At least one key element couples the yoke element to the housing element such that the yoke element is movable relative to the housing element. An idler wheel is rotatably supported between the first and second arms.