My family and I arrived back in DFW from vacation this past Friday to find our car with zero gas. It was parked at terminal D for five days, and there was NOTHING left in the tank. Now I know that one may think I forgot to fill up, but I did the day before to prepare for the trip to the airport. As we are waiting for AAA to help us out, I check to see if the fuel door locks. Nope. Wow...really?!?! Two-fold question....1- Anyone have their tank siphoned and is there a decent locking cap? Many options, but is any one of them better than the others?