Not sure about all those years you included but, in general, tanks are vented both ways in our old trucks. In and out. By the cap or other means. There are vented caps and there are vented caps. Some are one way. Some are both ways. You can get fooled by the words vented cap. Find how a particular tank is vented, both ways, and then get the proper cap depending on year. Some 70's cars have charcoal filters and one way caps........... and Government mandated emission control from there on. The older trucks vent to the atmosphere. My 2011 F150 4X4 has no gas cap.
