Coming across Lizard Head pass near Telluride, Colorado and noticed half the hot water heater hanging outside the side of the trailer. Went over two road heaves just West of Ridgeway headed North which probably precipitated the problem. When I went to repair, discovered hot water tank was only secured by two screws, one one each side. One screw had no purchase in the wall and had vibrated out!!! Installed 4 scews and made sure they were all screwed into the walls! As gas line and water lines involved, this could have been a real bad issue.