I've got a separate set of winter rims and tires, so I will be storing my summer rims and tires during the winter. I will most likely store them in my shed, where they will be exposed to sub freezing temperatures every night for four months. Are there any precautions I should take? Deflate them? Over inflate them? Coat the rubber with something?

 

I would just lay them down and ignore them. The cold won't hurt them any more than if they stayed on the car all winter. There won't be any weight on them to speak of.

I would just put down a piece of cardboard. Then put the first tire down with the inside facing the ground. Then stack the rest on top of it. Put the top wheel on facing down so it doesn't collect dust/dirt.