01-08-2007, 11:59 PM
True Car Nut
Join Date: Jul 2004
Location: Grand Rapids, Mi
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You may have the problem listed in this technical service bulleting, which says in part....
Steering - Vibration, Shudder, or Moan Noise
File In Section: 02 - Steering Bulletin
Date: February, 2001
Steering Vibration/Shudder/Moan During Parking Maneuvers on Dry Pavement (Install Power Steering Pressure (Inlet) and/or Return (Outlet) Hose Assembly)
1995-99 Buick Riviera
1997-2001 Buick Park Avenue, Ultra
2000-2001 Buick LeSabre
2000-2001 Pontiac Bonneville
This bulletin is being revised to add the 2001 model year and to update the parts information. Please discard Corporate Bulletin Number 99-02-32-007 (Section 2 - Steering)
Some customers may comment on a steering vibration, shudder or moan noise when steering during parking maneuvers on dry pavement.
Install a new power steering pressure (inlet) hose assembly on the following vehicles:
^ 1995-98 Buick Riviera
^ 1997-98 Buick Park Avenue and Ultra
Install a new power steering pressure (inlet) and return (outlet) hose assembly on the following vehicles:
^ 1999 Buick Riviera
^ 1999-2001 Buick Park Avenue and Ultra
^ 2000-2001 Buick LeSabre
^ 2000-2001 Pontiac Bonneville Diagnosis
Important : In diagnosing the above listed vehicles, do not overlook other obvious repairs prior to replacing the hose(*).
1. Verity that the power steering pump reservoir is full.
^ If fluid level is low, till and check for leaks.
^ If power steering system has air in the system, perform the "Bleeding Air from Power Steering System" procedure as described in the Power Steering System sub-section of the Service Manual.
Important : When performing the "Bleeding Air from Power Steering System" procedure, it is important that the front of the vehicle is supported by the lower control arms. If the vehicle is not supported by the lower control arms, the procedure may cause the strut bushing to dislocate and cause new concern.
2. Verify that the accessory drive belt is in good condition and that the pulleys are not bent or damaged.
3. Verify proper belt tension and operation of the belt tensioner.
4. Check for power steering hose ground out conditions.
5. Check for good engine idle and correct engine RPM.
6. Check to see that the rear transaxle mount does not have a plastic assembly aid installed which is used for assembly purposes. If the assembly aid is installed, remove the assembly aid and install the rear transaxle mount.
7. With the vehicle on dry pavement, maneuver the vehicle in parking positions. If the steering vibrates/shudders or moans in this test, replace the power steering pressure hose and/or the harmonic balancer.
Important : A defective harmonic balancer on the 1995 Buick Riviera can influence steering vibrations after power steering hose installation.
Important : When installing the pressure hose on the 1995 Buick Riviera, pull down on the pressure hose at the rear of the engine or bend the hose to allow clearance between the hose and the front of the dash.
Power Steering Pressure (Inlet) Hose Replacement Procedure