Big Boy, 4014 wheels rod actions backing to park

Worlds largest operational steam locomotive Big Boy , 4014 wheels rod actions while backing to park. BIG BOY No. ,4014 From Union Pacifics web page BIG BOY No. 4014 Twentyfive Big Boys were built exclusively for Union Pacific Railroad, the first of which was delivered in 1941. The locomotives were 132 feet long and weighed 1. 2 million pounds. Because of their great length, the frames of the Big Boys were hinged, or articulated, to allow them to negotiate curves. They had a 4884 wheel arrangement, which meant they had four wheels on the leading set of pilot wheels which guided the engine, eight drivers, another set of eight drivers, and four wheels following which supported the rear of the locomotive. The massive engines normally operated between Ogden, Utah, and Cheyenne, Wyo. There are seven Big Boys on public display in various cities around the country. They can be found in St. Louis, Missouri; Dallas, Texas; Omaha, Nebraska; Denver, Colorado