Hi Larry.
I am talking about the pads the shell sits on when closed. this thread has pics of them:
http://www.trailmanorowners.com/foru...ht=rubber+pads
Also make sure that the "hook" surface on the clamping piece is parallel to the frame. It has slotted holes for adjustment and if goes a little upward on the open end, that pin will slip out.
What year is your Transit and what motor you using? I have mine converted to an overnighter camper for quick trips. i liked it so much that I also bought a new Transit connect which are really hard to get here in Florida. What part of the country are you in?