[Tinker]

So your issue is you didn't over heat but lost fluid? If you leave it alone and don't add coolant then drive it hard again, do you over heat?

I don't think the 4lb cap came into the mix till 53 or so. I could be wrong.

Yes adding a 7lb cap could blow out a "old" rad. Pressure.

I don't think this is a pressure issue, as much as a volume issue. Just my 2cents.

Flow in the rad could be an issue. But did you try to run it hard after it puked. It can only take so much fluid volume. Over filling will find a way to dump. Reason for the overflow tube, but it just ran onto the ground normally before the pickup.

There is only a volume amount suggested by ford for coolant and oil. The gauges tell you if you over heat. Not if it's too much or too little on both. You have to watch that.


Having a heater to the cab helps to divert volume as well.




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