There are actually specific areas of track called "dark territories" where the trains lose all signal contact and could potentially be in danger of attack. The original title for this episode was Dark Territories, but it was changed to Dead Freight because it is a train term describing an empty freight car, which you usually have to pay to ship anyways. One of the boxcars was visibly empty because the crew could not get the rusted door cover to close on the train.
The train engine, built in the 1950s, broke down on the first day of shooting and set back production. In addition, the production crew ordered 12 boxcars to use and they were expensive to rent. When they came in from Texas, they were covered in graffiti. At first, they thought it would be too much to paint over, but then they couldn't get clearance (from the artists!) to leave the graffiti as is, so they ended up painting over it.
Original ideas for the train heist involved a helicopter flying over to the depot where the train car was held to suck out the methylamine midair. They didn't think the train idea was going to work for budgetary reasons, however, the estimates for robbing the methylamine out of a truck was almost just as expensive.
This episode was nominated for an Emmy in the Outstanding Writing in a Drama category.