A railcar positioning system operable as either an indexer or progressor is disclosed which includes a pair of spaced trackside railcar movers positioned outside and parallel to the rails of a railroad track. Each railcar mover includes a spaced trackside guideway located next to one of the railway rails, a plurality of spaced connected dog carriages mounted for operation together in the guideway, each dog carriage carrying a pusher dog mounted on the carriage, a reciprocating hydraulic cylinder associated with the plurality of spaced, connected dog carriages. A hydraulic power unit is connected to operate each of the cylinders individually or together and a control system is associated with the power unit for controlling the operation of the positioning system such that said positioning system may be optionally operated as an indexer or as a progressor.