No theft. but before we could build our rv barn, I am pretty sure someone was trying to punish us for having it parked in front of our house. ( and we dont live in a community where you are not allowed to park there and our houses sit on at least 2 acres each) Some one dumped what we believe to be sand into our fuel tank. It was pretty costly to have the tank dropped and cleaned and replaced. Not to mention the tow when the thing just stopped running because of the blockage. So, we dont have a locking fuel tank, but we do have a very good security system at homeand in the RV barn.