It's always good to know what to do in that case. The last time I drained antifreeze from a machine was in 1977 when we got our Steamway Turbomatic in mid winter. My only concern now would be if my Chevy Express broke down on the road on a cold day, with van engine disabled. (that has happened to me already, but it was still above freezing by the time it was towed). At least with a slide in, you can start tm engine and keep inside temps up.