Thanks for everyone's replies!!!
Over the weekend I did the following and it did not help:
1. Removed and cleaned the reservoir filter with mineral spirits, then rinsed it several times with ATF once it evaporated.
2. Ran almost a gallon of new ATF through the pump while turning the wheel. A lot of ugly fluid came out. The pump is definitely still working.
3. Lifted the car and visually inspected the hoses, pump, etc. The u shaped hi pressure hose is a bit wet like it is seeping fluid. Everything else looked great.
4. Belts look great and have a ton of tension.
5. Put everything back together and filled it with fluid.
Still makes the same loud growling noise after the filter flush. The pump definitely still works because I'm getting steering assist and fluid is definitely circulating in the reservoir.
My best guess is that the pressure hose is coming apart on the inside and restricting flow to the pump.
Anyone have other ideas before I start throwing expensive parts at it?