If its a coleman road trip grill this link will show you what you need to do. You basically unscrew the regulator off of the pipe that screws into the grill burner and attach a hose to the remaining pipe. It will now work on the low pressure hook up on your trailer. I have done this very thing. Works great with no problems.
http://www.rv.net/forums/index.cfm/f...d/25114578.cfm