The D&RGW did move locomotives dead in train on occasion. The locomotive assigned to the Pagosa Springs Branch was apparently moved from Pagosa Jct to alamosa in the manner described above. The main rods were dropped, some sort of lubrication was provided for (I presume) and the locomotive was moved in a freight train to Alamosa. After being shopped the process was reversed. See description and photos in "Logging Along the Denver & Rio Grande" dealing with this.
I don't know how common this was, because I recall reading accounts of moving small power (C-16 or so) from Gunnison to Salida for shopping, and the problem was the worn driver tires did not grip the rail well when climbing Marshall Pass. In this instance, the locomotive ran light from Gunnison to Salida.
Charlie Mutschler
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