If you totally ignore the warning signals and then see steam coming from under your hood, and your Caddy then stops going, then you might well be out of water! Ron
It is at the end of the lower radiator hose on the motor. You will have to empty the radiator and remove the housing to replace it.
The position of the Thermostat depends on the engine. In the 4.7liter it is near the bottom of the engine. Follow the hose From the radiator. Where it connects there are two screws. Remove those and the thermostat is under this piece. On the 3.9 v6 and 5.9liter it is at the top radiator hose where it goes into the engine. Empty coolant first.
Your radiator appears empty because your cooling system has a leak.
NO
You may be low on coolant. Check the reservoir and the radiator, if it is empty check for leaks in the system. If it is full you may have a stuck open thermostat causing no heat.
Over-obvious answer? Your radiator, or one of your radiator hoses, leaks - badly.
you need to remove the lower coolant hose on the radiator and remove the 2 10mm bolts on the thermostat housing (empty coolant first) then the thermy is located right in the housing which you use a cylindrical cardboard tube the new thermostat comes with to push in on therm and rotate which frees the therm up and push the new one in and rotate the tube to lock it into place
You need to check the radiator and be sure it is full. It can be empty and the overflow tank full. If it is full then check and be sure the radiator cooling is working when the engine is at operating temperature.
If the entire system (radiator, engine block and heater system) is empty it will take 11 to 12 qts to refill (this also depends on what engine you have and if it has ac or not). If you only drain the radiator, aprox 5 qts.
pull the petcock on the bottom of the radiator. it's either on the feft or the right bottom
Should be a plug at the bottom or rear of the radiator
I AM NOT familiar with this exact vehicle, but as far as the petcock goes, if the radiator is plastic, there may not be one at the bottom. You may just have to remove the bottom hose and drain it from there. As far as the thermostat goes, ask a Ford dealer or invest in the big orange book called "CHILTONS". You can find a Chiltons at major automotive stores. The book is expensive, but well worth it if you do your own repairs on a regular basis. GOOD LUCK