2005 Jeep Wrangler Gas leakeage following fill-up

The pump will continue to pump till it recieves so much pressure back and then the pump will kick itself off. Two tubes going to the tank, one is a main fill tube and the other is a vent tube that allows air ezcape while filling. What happens is that last little bit of fuel that is pushed into the tank right before the pump is shut off actually gets forced back up through the vent line and of course there is no room so it gushes out the fuel tank opening. No way to stop this except to manually slow the fuel down when the tank is about to get full and just putting in a slower amount of fuel so it kicks off but does not spit up as bad. I think this is the answer to your question and I hope it helps you. Curt