A natural by-product of engine exhaust is plain old water.
So if you are seeing a leak at the 'cat', and if it is clear liquid, it should be water.
Anything that doesn't look and feel like water is a sign of a problem, i.e., anti-freeze and/or engine oil getting into the cylinders and pushed out the exhaust.
That would be time for a visit to your local mechanic.
If a transmission is leaking fluid, it is likely that a seal or gasket has failed. Replace the gaskets and seals and the leaking should stop.
A Ford Taurus transmission holds between 10 and 12 quarts of fluid depending on the model. Additional fluid is stored within the torque converter which is not drained during a fluid change.
It could be transmission fluid or coolant, or a problem with the catalytic converter.
your heater core is leaking i would replace it.
A torque converter itself VERY rarely leaks. It's possible, but HIGHLY unlikely. If you have fluid leaking there, it is most likely the front transmission seal. The casing of the converter itself is basically two halves welded together, if the converter itself is leaking, there is most likely some pretty significant damage, so the leak would be the least of your worries. You can always check by disconnecting the battery and wiping the converter clean with a rag then slowly turning the flexplate. If it really is the converter itself, you will easily be able to see where it is leaking.
The better question is what is leaking transmission fluid?
The Torque Converter uses the same fluid as the transmission. The transmission has a filter. So, in effect...the answer is "Yes" torque converter fluid is filtered. However, the torque converter has no special fluid of its own.
A plugged/damaged catalytic converter is one possibility.
Sounds like the system is getting air in it from somewhere. Check to see if you see fluid leaking from any point of the system.
WHICH fluid.
The transmission fluid for the 2000-2004 Taurus is MERCON V.
Probably your radiator fluid leaking out.