Trackmobile

A railcar mover is a road-rail vehicle (capable of travelling on both roads and rail tracks) fitted with couplers for moving small numbers of railroad cars around in a rail siding or small yard. They are extensively used by railroad customers because they are cheaper than owning a switcher locomotive, more convenient and cheaper than paying the railroad operator to do the switching, easier and more productive than manual moving of cars, and in addition they are more versatile since they can travel on road wheels to the cars they need to move, instead of needing clear track.

Some have two drive systems and drive only on steel wheels on the rail, with their rubber tires lifted out of the way, while others have only one drive system and use steel rail wheels only to guide them and use their rubber tires on the rail, in a similar fashion to HiRail trucks. These systems have a higher tendency to derail while pulling loads and in curves.

Railcar movers are fairly lightweight, so in order to gain more traction some models transfer weight from the car they are hauling onto their own wheels to increase their effective weight. These models use steel wheels on steel rail, much like a locomotive, which provides a more consistent traction among wider variety of conditions. The steel wheels also last far longer than rubber tires and overall cost less to operate. In Australia, construction equipment such as loaders and telehanders are converted to shunting use and on these machines, the boom lift is used to transfer weight from the car to the drive wheels. In Europe, trucks (lorries) fitted with railway wheels and couplings are used as rail car movers (often called towing or shunting vehicles).

Numerous manufacturers produce railcar movers, in multiple countries. The first railcar mover was built by Whiting Corporation, now Trackmobile in 1948.

Well-known railcar mover brands in North America include Trackmobile, Rail King and Shuttlewagon.

Trackmobile is a well-known railcar mover worldwide and began as an in-plant project at Whiting Corporation, Harvey, Illinois. In 1947 a young ex Navy fighter pilot and engineer named Marshall Hartelius was assigned to modify an old industrial locomotive Whiting had used for years inside their plant. Their locomotive was constantly being trapped on dead-end tracks, losing hours of productivity. Hartelius was charged to find a way to move it by road to avoid bottlenecks to railcar movements. He first designed a road wheel system to mount on the locomotive, but found it was cumbersome and complicated. Furthermore, in spite of the added utility of road-to-rail capability, the locomotive consumed a lot of fuel and oil and required constant repair. Marshall scrapped his first design and in its place submitted to his boss a concept for a vehicle specifically designed for in-plant rail movement. It had hard rubber tires to move by road and flanged steel wheels to work on rail.

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Wikipedia