Yeah, it is a big locomotive. I was wondering if anybody here might have some inside info? I'm suspecting that they are bleeding-off a lot of steam to keep the pressure lower than it was originally designed to run at. It seems that every time they take it out, it's paired with a modern diesel which is well capable to handle the majority of the draw, and that 4014 is there mostly for show, maybe adding a bit of extra pull when needed. A few years ago, UP connected their one working Challenger to a container train solo and got some really good film from that, but so far I haven't seen 4014 pulling anything alone.