Lonesome Trailer

Brendel buys a trailer that can expand from a small wagon to full size caravan. He takes his wife and daughter on a vacation trip, with complications like getting unhitched from the car while in traffic, and the trailer shrinking back to it's original size unexpectedly. They park for the night at a trailer park, but El sneaks out to a nearby roadhouse. All is fun fun, drinking and dancing, until his wife follows him there. - IMDb