There is a TSB on that subject. The repair depends on what engine is in your car...
Moan/Squawk Noise During Low Speed Turning Maneuvers (Replace Power Steering Gear or Pressure Hose AssemblyP #02-02-32-002 - (Jan 14, 2002)
2001-2002 Oldsmobile Aurora
with 3.5L V6 or 4.0L V8 Engine (VINs H, 6 -- RPOs LX 5, L47)
Built Prior to the Following VIN Breakpoints:
Engine VIN Breakpoint
Some owners may comment on an audible moan/squawk type noise that is heard during low speed turning maneuvers.
This condition may be caused by instability of the power steering gear valve. This may result in a pressure disturbance that creates an audible noise that is transferred through the vehicle structure.
Based on the engine type indicated below, replace either the power steering gear or the power steering pressure hose with the components indicated.
4.0L V8 Engine (RPO L47) Built Prior to VIN Breakpoint 24100112
Install a new power steering pressure hose, P/N 25737839, and secure the clip of the new hose to the frame with new screw, P/N 11515764, using the hole in the frame where the existing clip had been installed. The clip is to be positioned in a fore-aft direction with the hoop of the clip pointing forward and the attaching screw tightened to 7 N·m (60 lb in). To ensure the proper installation, refer to Power Steering Pressure Hose Replacement (L47) in the Power Steering System sub-section of the Service Manual (SI2000 Document ID #628527).
3.5L V6 Engine (RPO LX5) Built Prior to VIN Breakpoint 24131699
Install new power steering gear, P/N 26098941. To ensure the proper installation, refer to Power Steering Gear Replacement in the Power Steering System sub-section of the Service Manual (SI2000 Document ID #620339).
Part Number -- Description -- Qty
26098941 -- Power Steering Gear -- 1
25737839 -- Power Steering Pressure Hose -- 1
11515764 -- Hose Clip Bolt -- 1
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