Union Pacific 'Challenger' Production Models 

The version #6 models are 'late' configuration oil-fired locomotives. While similar to the version #5 passenger models, this variation utilized a different 'ATC' system represented in the included detail that will be shown in greater detail in the following photos. These prototype locomotives were in large part the same locos used in passenger service, but they were repainted all black after being withdrawn from passenger service and had many of the updates applied that were used on the coal-fired locomotives. There were a few prototypes converted to oil after the Challengers were withdrawn from passenger service and we have included some of those road numbers in our production. We have modeled variations both with and without smoke lifters.