Tech Tip: Cadillac DeVille Makes a Moaning Noise

Tech Tip: Cadillac DeVille Makes a Moaning Noise

If a customer complains about a moaning noise in his or her 1998 Cadillac DeVille, it may be due to the steering system frequencies.

Customers may comment on a steering vibration, shudder or “moan” during low speed turning/parking maneuvers. This condition may be due to the steering system frequencies being transmitted through the power steering pressure (inlet) hose assembly. An improved power steering pressure (inlet) hose assembly is available from GMSPO. To replace the steering pressure hose, refer to the repair procedure.

The following parts will be required to complete the repair:

P/S Inlet Hose Assembly P/N 25755411

P/S Inlet Pipe Adapter Plug 26021965 (00-02 Eldorado only)

Double Ended Stud 11518592

1 Nut 11517293

Applicable Vehicles: 1997-’99 Cadillac DeVille

                                    1997-2002 Cadillac Eldorado

Repair Procedure

Removal Procedure:

1. Open the hood and install fender covers.

2. Disconnect the power steering pressure (inlet) hose (1) from the power steering pump (2).

3. Raise and support the vehicle.

4. Remove the bolt (3) that retains the pressure hose retaining clip to the engine block.

5. On 1997-1999 DeVille and Eldorado models, disconnect the pressure switch (4) electrical connector.

6. Remove the exhaust shield retaining bolts.

7. Remove the exhaust shield from the vehicle.

8. Remove the pressure hose plastic retaining strap (5).

9. Disconnect the power steering pressure hose (6) from the steering gear.

10. Remove the power steering pressure hose from the vehicle.

11. Remove the power steering pressure switch (7) from the hose assembly.

Installation Procedure:

1. On 1997-1999 DeVille and Eldorado models, install the power steering pressure switch (7) to the new power steering hose assembly, P/N 25755411. Tighten the pressure switch to 10 Nm (88 lb.-in.).

2. On 2000-2002 Eldorado models, install the plug and O-ring assembly, P/N 26021965, to the pressure switch adapter on the new power steering hose assembly, P/N 25755411. Tighten the plug to 11 Nm (97 lb.-in.).

3. Position the new power steering hose assembly into the vehicle.

4. Connect the power steering pressure hose (9) to the steering gear. Tighten the pressure inlet hose at the gear to 27 Nm (20 lb.-ft.).

5. Install the pressure hose plastic retaining strap (10).

6. Install the exhaust shield to the vehicle

7. Install the exhaust shield retaining bolts.

8. On 1997-1999 DeVille and Eldorado models, connect the pressure switch (11) electrical connector.

9. Install the double end stud (12), P/N 11518592, to the engine block. Tighten the stud at the engine block to 50 Nm (37 lb.-ft.).

10.  Place the pressure hose retaining clamp ends over the small end of the stud (12).

11.  Install retaining nut, P/N 11517293, to the stud and tighten.

12.  Lower the vehicle.

13.  Connect the power steering pressure (inlet) hose to the power steering pump. Tighten the pressure inlet hose at the pump to 27 Nm (20 lb.-ft.).

14.  Fill the power steering system.

15.  Bleed the power steering system.

Courtesy of ALLDATA LLC.

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