As far as I know, the screws go into whatever is being used for a floor--maybe only 3/4" plywood. If the screw hole is stripped, the first thing to do is to try a larger screw. That may not help for long--stripped out once, will prob strip again. Possibly try liquid wood, or some type of filler in the hole, then replace the screw. Tough situation...
2016 Tiffin 40 QBH
2015 38RSSA, traded
2005 TK3 #1869, 10 yrs of memories,
2017 F450 KR--one more Ford is it
2009 F450 4x4-died; 2010 F450-retired