2001 Ford Taurus stationwagon steering noise

I have a 2001 Ford Taurus SES station wagon with 84,000 miles. When I turn the steering wheel at speeds less than 5 mph, I hear a moaning sound form the steering. This happens when I turn either left or right. Three mechanics have said that this is a chracteristic of the car and not to worry. Should I wory about the noise?

Thank you.