To avoid brakes freezing when I was trucking in the northern states, I had wood blocks to use as wheel chocks. Then I would insert 20 gauge sheet metal shims about a foot long and an inch wide in between the shoes and drum, then set the brakes.
I would poke them in about 4” with the last 8” bent out at an angle for a handle end. Set the brakes, plug in the truck (if going to the house), and come back the next day, start up the truck release the brakes and pull the shims. Set the brakes, and remove the wood wheel chocks.
If I needed to use my hammer, it was to knock out a chock(s). But I didn’t have to crawl under the truck for that!
So many tricks.
Ever do the redirected truck exhaust one to unfreeze locked tank valves?
I worked for a small oilfield company where we all shared trucks and trailers and somebody forgot to finish their trip during freezing weather with the turpentine into the empty tanker.