on the ladder that is mounted to the rear of our camper, it pulls from the camper when we start to climb on it, and there is one screw that is loose, and wont tighten up..
was wondering is anyone knew how they mount these things ?

can we move this to ask a dealer ?

Sounds like the person that installed the ladder didn't mount it to a framing member. Your fifth wheel is built similar to a house, with "studs" in the vertical direction. The ladder should be attached to a stud. Kind of like mounting a shelf or something similar in your house, you need to get a studfinder and locate the studs, and then use screws long enough to attach to them.

I agree with Jasoncarder on it probably not being in a wall stud. One thing that may have happened is that since it was most likely on a production line the person may have barely dug into the wall stud. It may have held at first then when weight applied it may have worked loose. If that is the case and it is there just pull the screw out and screw it back in at a angle towards the wood. Then silicone around the screw to prevent leaks. Be careful if you change the screw out. IF it is longer it may go all the way through the other side. I watch out for that when I rebuild one of these. If you can see also be careful of wires. If there is a plug close and also check wires underneath to see if they go in that area if you can. The older ones are fairly easy to figure out where the wires are.