Front end groaning in a '92 LX Wagon

My sweet old '92 Taurus wagon is making a god-awful groaning noise when I turn the wheel to the right. This little musical rendition has graced my driving for several years, and I have learned to ignore it with little difficulty. Lately, I have noticed that the groan no longer requires the wheel to be turned to the right, I can hear its voice even when the wheel is straight. I suspect that the steering rack may have reached its useful lifespan (131,000 miles) since the power steering pump appears to be in good order, and the noise no longer requires that the pump be pressurized. Anyone have any thoughts on this? Thanks.