I'm in Alberta, and a polar vortex has come to visit. -42C this morning, but it might drop to -50C in the next night or two. My truck is new to me, so I'm not sure what ratio the (clear red) antifreeze is. I put a drop on a can to observe; if it starts freezing I'll have to do something. I don't have a shelter for the truck, so I could stick blankets over the engine and radiator and spend some sleepless nights heating water to stick under it. I suppose I could warm it up enough to start and then drain a bit of coolant and add more antifreeze (all I have is some green). Any other suggestions? Does antifreeze protect from expansion damage beyond its freezing range? Tire traction drops with temperature, so I don't want to drive until the weather warms up a bit. Trying to change coolant when water freezes immediately on contact with cold metal is not a good plan. Plastic bits might be brittle too.

The 91 V6 started fine at -25C, but after running for a bit then shutting it off, it wouldn't start maybe 1/2 hr later. Eventually it did start again, and no problems after that. I'm guessing the cooling engine sucked in extra fuel. For extra hassle (I needed to drive into town to pick up parcels), the ignition wouldn't unlock. A squirt of WD-40 got it to move. It's cold out here.

 

I have heard that strong antifreeze solutions cooled below their posted freezing points never freeze harder than slush, and so they
continue to offer some protection against damaging hard freezing that ruins radiators and cracks blocks.
I have no personal experience to support this position though.
Perhaps others with actual super-cold life experience will chime in.
It would not be wise to dilute the red coolant with green.
Blankets on the engine and an incandescent lightbulb or two would help.

 

It only dropped to -44C, and the sample stayed fluid. The latest forecast is less severe, so I'm less worried about possible -50C. A definite scare though. I'm 25 km out of town, so if the radiator burst, I can't just go pick up a new one. Next coolant change I'll go with a -50C mix, just in case these -50C scares are more frequent due to global warming. I'd lived here nearly 20 years without going below -40C, then last year had -43C.

 

did you take it to a professional ?