In the four years I had the truck, no leaks, no adding of fluid, No leaks anywhere on the engine area on PS hose or nuts. Still no leaks now after this mystery of the flluid coming out the top vent hole on the cap.
It had to have some kind of pressure when the temp rose from 12 degrees setting there for 4 days and then the temp went above freezing that day. I agree that some kind of check valve etc broke loose when I ran the engine up high RPM and the fluid that was up to the filler cap edge just dove down into the bottom of the tank and thus I was able to put 1/2 quart of ps fluid back into the tank to the fill level.
Does any one have any drawing etc of the PS system. If so this could clear up just
what went on during that freeze up and thaw.
Thanks