Methyl hydrate (fuel line antifreeze) is necessary, for sure. I was up Williston Lake at a logging camp in the late 90's, where we never shut the vehicles off.
The temp was pretty low, too low to work outside, -52 C seems to me. That's about -61F or so.
A logger, truck running low on fuel drove over to the pump and when he grabbed the pump handle, the hose broke off at the pump, spewing fuel oil. He got it shut off and grabbed the other hose on the other side of the pump. Same thing happened.
Better luck at the other pumps, either newer hoses, or out of the wind. Wind at that temp is a killer.
Problems with breaking truck frames, springs, etc. Steel give up at those temps.