Water pump, thermostat, radiator issues, there is a few possabillities
first do you have a gauge or a light on your dash board.
If you have a gauge, when the truck is cold and you start it up. it will run for a few minutes and the gauge will show cold, cold, cold, then after a short while it will suddenly jump up to operating temperture, If it does this then your thermostat is most likely working. If it slowly creaps up and then overheats, your thermostat is bad.--- If you have a light on the dash, then you want to open the radiator cap before you start the motor( when its COLD). And watch the flow. A bad thermostat will only let a very little bit of flow happen.
A bad water pump will usually leak out of the breather hole on the pump. But not always.
As far as the radiator being bad, personally I would change the thermostat first, because even if you find out something else is wrong later on, you would wind up replacing it anyway as a precautionary measure.
I am not familar with a power ram, does it have an electric fan, and is it working?