First off, is the case of the overheating locomotives. Western railroads with long tunnels and snowsheds (particularly Denver & Rio Grande Western, Southern Pacific, and SP subsidiary Cotton Belt) had cooling issues with locomotives produced by GM's Electro-Motive Division - in particular, the 3000-horsepower GP40 and SD40 and the 3600-horsepower SD45.
EMD kept their radiator intakes mounted higher on the locomotive carbody than other manufacturers, just down from the roof. This meant that when the radiators drew in air for cooling, it came from the air at the top of the tunnel, which was hot from diesel exhaust and air already warmed by being run through the radiator. This caused some problems, to put it mildly.
The D&RGW tried out a water spray system on their GP40s as a first attempt. This consisted of a cool water tank, and a series of nozzles that would drench the radiators. While it worked, the limited capacity of the tank and the soaking of the radiators and surrounding steel made it less than an ideal solution. Southern Pacific found some success with large shrouds over the radiators of their SD45s.
Meanwhile, engineers at EMD were working on a better solution. They began by redesigning the radiators to draw cool air from the lower carbody sides, with large ducts to suck in the cooler air near the bottom of the tunnel. The catch was that some equipment normally installed in the carbody section below the radiators would be displaced forward, making the rest of the internals mildly cramped. The resulting locomotives, the SD40T-2 and SD45T-2 (the GP40-2 never received such a fix) solved the problem marvelously, and due to their distinctive-among-EMDs radiator profile, they received the nickname 'Tunnelmotors'.
At the other end of the train once sat the caboose. Used mainly to provide a lookout at the rear of the train, and shelter for crews at the rear end, these cars were a classic and familiar sight in railroading. Crews eventually gave a large number of nicknames to these cars, many of them pejorative, but some fond as well:
- Bobber (usually reserved for 2-axle cars)
- Monkey Wagon
- Brain Box
- Van (Canadian, possibly derived from the term for the British equivalent of the caboose, the brake van)
Of course, technology marches on, and a replacement for the caboose was eventually developed. This device was a battery, strobe light, and small computer that monitored air pressure in the brake system. These were called Flashing Rear End Devices. Train crews, however, quickly turned 'Flashing' into 'F*****g'. The main reason being that the damn thing was the whole damn way at the other end of the damn train from the locomotives. It was also damn heavy and a trainlength was a damn long way to carry the damn big thing.