You can unwax a filter, but it takes heat. The once I gelled it was -5 and I had summer fuel and Bio in my truck. I got some 911 and was able to get my truck started it just wouldn't do more then idle. After 1hr or so of idling I could drive it easy. After a few hrs of short trips and idling it was fine unless I went WOT. I finely used my wife's hair drier to thaw out the filter. It worked pretty fast too. Smelled a little like diesel though the next time she dried her hair. She was a trooper and didn't make me buy her a new.:hug:
I've had lots of equipment and semis we've had to build "tents" over and stick a heater on to get them to thaw out. Honestly I have never changed a filter on something that gelled. That I can think of.
Indiana I'm sure your getting winter fuel most places switch over and don't list it anywhere. Truck stops don't sometimes don't since trucks are kept running a lot of the time. Also you might look into 12v heating pads like oil pan heaters. It may have been on DP that some guys where resorting to this, because they where gelling running down the road even.