I'm working on my son's 2003 Ford Taurus 3.0L V6. The power steering pump is whining, we have to add fluid to it every once in a while, when he shuts the car off though the fluid in the pump seeps out the pump reservoir cap, is this the pump causing an issue, or is it a pressure line issue, also what is that cylinder like object mid way between pump and rack for?

Use this list to identify the parts

https://www.partsgeek.com/catalog/2003/ford/taurus/steering/power_steering_filter.html

I think you mean the power steering filter, so please confirm. Does your (RESERVIOR) cap have a gasket (YUP)? Probably need to be changed. O rings and gaskets are usually the cause of power steering fluid leaks. You must clean the parts to find leaks to address them accordingly.

Let me know what you find.