legal obligations of trailer dealer???

[coachrandall]

I have a 2009 Ford F150 super cab, 5.4 eng with 3.73 rear, w/ max tow package. this truck is rated for pulling 11,000 lbs. Gross vehicle weight 7200 lbs, tires rated 114 T (2601 lbs). Aug 2009 my wife and I went looking for a trailer. we looked at reguler trailers but liked the bunk house layout on a new 2008 KZ sportsmen 255BH 5th wheel that was on the lot. the salesman stated it was only 6900 lbs dry weight and my truck would not have any problem towing it. he set me up with the whole package, a Slide Right hitch for my 6.5' bed, brake controller and the trailer. about 2 months ago i was reading forums about exceeding GVWR and started doing some home work. even though the trailer is 6900 lbs dry weith the dry hitch weight is 1963 lbs !!!! Almost 30 percent of the trailer weight. add in the hitch and i'm about 500 lbs over my GVWR. Shouldn't the dealer be responsible for selling something so over weight for the tow vehicle or am I screwed for trusting them?

I need some help on how to handle this.

thanks