RV (2006)

Bob Munro is the dad of a dysfunctional family. He hires an RV to take the family on vacation. However Bob is NOT the best RV steering wheel operator in the neighborhood and the hilarity is added on by the fact that the brakes are about as useful as a chocolate fireguard. Bob first realizes it when the RV rolls (not literally) backwards into a line of shopping carts. Also Bob's job is in danger if he doesn't go to a very important meeting. Before you can say "COME BACK! COME BACK!," things go gloriously, hilariously, Munro-annoyingly wrong due to the lack of brakes, Bob's job, toilet waste not cleared out from the last rental and more hilarious stuff.