Union Pacific 3642's glory days of hauling high speed traffic on the mainline are a distant memory now. Years ago, this SD40-2 was set up as an RCL switcher, and has been held captive at UP's former D&RGW Roper yard, batting cars around day in and day out for years. On the plus side, 3642 is still in active service whereas many of it's siblings currently rust away in deadlines across the UP system.