I thought I mentioned that they were hoppers, and there might be something to do with the unloading devices behind that hole. (As Sheetrock Ed said, they might still have a rotary coupler.)
We can scratch the possibility that this is a new design: from what I could find out on the computer at work, these cars were built in 1990, and were relettered FURX in early 2001. I tried to get a line on their ancestry, but that will have to come from someone with full access to UMLER records.
Forgot to ask: were these aluminum, or steel? My screen at work shows steel, but it isn’t always right about such things.
Sorry BC - I read so fast, I read right over that part.
Ok - they were hoppers and were not aluminum. They were a dull brown-red color, didn’t look very new and went by pretty fast. He was going out of town, so had picked up quite a bit of speed by then and they were about 3/4 of the way back. I was sitting there daydreaming and suddenly noticed the holes! Looked like someone had come along with a big punch and punched a nice round hole in each one. Like they would put them on a big round key ring and hang them from a nail…(gotta get more sleep!)
Did it look like they had a little extra steel around the hole, as if the car body was “thicker” there?
If , you might be looking at the tow loop, or tow eye, where the car has a eye or hole designed for the tow chain to be hooked to…