gishark wrote:
I have the same shifting problem that you are having with my 2000 10.6 Bigfoot on a 2006 Ford. You stated that you are using 2 inches of foam along with the mat to clear the cab. I am using 2x6s, topped by plywood and then the mat. Your platform must be a lot lighter than mine. What type of foam are you using? Looking forward to seeing your solution.
There are a couple of threads that discuss this in more detail but to answer your question, Home Depot has 2'x2'x1" pink insulating foam squares with high enough PSI to handle the weight. I ended up stacking them 3 high, gluing them together to get a single 2'x2'x3" block. I then placed a rubber mat in my bed, then 8 of these pink foam blocks glued together and then placed another rubber mat on top of that which the camper sits on. Other threads go into some discussion on the merits of using foam over more traditional methods. Some like myself have had great luck with it while others question the rigitidy of it. I think the conclusion is the right type of foam with a high enough PSI rating is more than adequate but it is suggested you use a piece of plywood ontop of the foam to keep it from compressing in localized areas. I haven't gotten around to using plywood and have not noticed any negative effects on the camper thus far. What I like about my system is that if I take the camper off the bed of the truck, I can store my entire system inside the camper and the foam itself doesn't weigh more than 10lbs I would guess. Much lighter than trying to build a system using wood and much easier to setup / remove as needed.
Getting back to topic, it is possible that my setup may be part of why the camper is sliding around but as previously stated, the amount of movement is less than an inch (measured). This slight movement isn't a problem of itself (other than bothering my OCD) but if it goes much beyond that (it hasn't) it could cause problems of opening the rear doors on the truck.
