04904, along with several others of the 4100-class have continuous drawstem draft gears in that the couplers are attached to each other by a long rod that runs the length of the car. Somewhere in the middle is a spring assembly that forms the draft gear function. If I recall the whole works is hanging on a single steel key driven into the assembly. Loose the key, break the rod, the couplers pull out of both ends, and out come the chains to tow it to the next siding.
Back in the earliest days of the C&TS in 1970, they pulled the drawbar out of 04904 when the last delivery of equipment came Antonito. It seems 04904 got between a SG GP9 and a string of cars including OY and a dead engine or two. They found out the starting tractive effort of a GP9 was much greater than the drawstem capacity of 04904. For many years, it languished on the tail of the Antonito wye as a tool car for the engine when it spent the night there.
Eventually it came to Chama and got put on one of the car repair tracks down in the Swamp. In the summer of 1981, arsonists torched a shed down there that happened to be right next to 04904, burning all the siding off the car. It's repair and restoration was one of the first projects taken on by what eventually became the FOCTS.