When I took off the truck camper this weekend my wife looked under the camper and noticed this! My truck bed has a very heavy duty truck bed mat and nothing was between it and the camper when...
Since it doesn't look structural, at this point, so I can start using the camper for this summer, I taped the crack with a 4" wide strip of Ultra Bond. I will also buy a pre-cut sheet of aluminum at Home Depot and fasten it to that side as well. Maybe put one on the other side so it is even.