it's called a road draft tube.
The length and angle of the lower (this has been cut off) is designed to create a suction when the truck is moving.The suction pulls out the fumes and moisture from the engine crankcase.
Was last used in 1967.
Since the one in the pic has been cut and capped,it is useless.There's no pcv that I can see.Does it have a hose from the valve cover to the intake or carb?
Mike.
