I finally found it....frame sag at the front overhang

[Bob&Patty]

John, I could not push mine in either until I removed all the screws holding the molding trim piece on. Then it was "katy bar the door". I had over a 1/2" movement in and out. Thats when I really started looking for "WHY". Best I can tell you.

 

[wdk450]

I looked up the 1/4 by 4-1/2 inch lag screws on the McMaster Carr catalog in 18-8 stainless steel, if anyone is interested. They cost $7.42 for a pack of 10. Here is the link:
http://www.mcmaster.com/#stainless-steel-lag-screws/=92df6c

You can also get all sorts of stainless steel self-tapping screws from McMaster-Carr for the underside covering and the trailer exterior. A lot of these on the trailers seem to have the heads rust/break off. The online catalog is pretty easy to use.

 

[Bob&Patty]

Bill, thats not a bad price.....75 cts ea. The screws I bought were .40 cts ea. Thanks for the info.