Last week, I bought an '04 TJ "X" and it has a similar problem... although it's a bit inconsistent. It groans during slow-speed turns (both L and R), but ONLY if I've been driving the Jeep for a while. No noise when driving straight, and the noise is louder on slower turns. If the Jeep has been sitting for an hour or two before I drive it, there is no noise during turns at any speed. The groans are loudest after I've been driving at freeway speed... after exiting, the groaning almost becomes a popping sound during a slow turn.
The PS fluid level is fine... I've checked it a few times. I've jacked up the front end and tried to 'rock' the wheels back/forth (checking for u-joint play), but they seem fine. The Jeep drives straight & true... no shimmies or wandering at any speed. Stock wheels & suspension (no lift... yet).
I will try the lithium lube on the steering wheel grommet (at the firewall), but it seems my symptoms are more than just a grommet needing lubrication. I sure hope I'm wrong. In the meantime, I'd welcome any ideas for other things I can/should inspect. Thx