51, 3/4 ton, 235, new gas tank, I have filled the tank with gas in the cool of the morning, parked in front of the house. The truck is sitting at a slight angle against the curb. The day has heated up and the truck is in the sun, gas starts leaking out from the filler cap. I did not top off at the gas station. The immediate fix I did was to pull that side of truck up on to the curb, no leak. What is going on and what can keep this from happening. Different kind of gas cap????
