Rattle/Knock Noise When Turning While Driving Over Rough Roads (Replace the Power Steering Return Hose, Install Fluid Restrictor and Retainers)

This bulletin is being revised to include the repair procedure and part information. Please discard Corporate Bulletin Number  02-02-32-012 (Section 02--Steering)

Some customers may comment that they hear a rattle/knocking noise when turning the steering wheel while driving over bumps. This noise is most easily replicated on a bump, hard-packed gravel surface.

This condition may be caused by hydraulic noise within the steering rack.

Follow the service procedure below and replace the power steering return line and install a fluid restrictor and retaining clips, if necessary.

1. Open the hood and install the fender covers.



2. Remove the resonator and duct assembly.
3. Place a suitable drain pan under the power steering pump assembly.



4. Remove the clamp (4) and the power steering return hose (3) from the steering pump (1).
5. Inspect the pump return line nipple for the presence of a fluid restrictor. If a restrictor is present, remove the fluid restrictor so it does not fall out of the pump during the repair.
6. Raise the vehicle on a hoist. Refer to Lifting and Jacking the Vehicle in General Information. Refer to SI Document ID #630747.
7. Support the exhaust system with a suitable adjustable jack stand, auto transmission only.
8. Remove the two nuts securing the exhaust pipe to the manifold, auto transmission only.
9. Remove the exhaust hangers from the exhaust pipe and reposition the exhaust pipe out of the way, auto transmission only.
10. Support the rear of the engine cradle with a suitable adjustable jack stand.
11. Remove the bolts securing the right rear corner of the engine cradle to the body and lower the cradle.



12. Remove the fastener (5) retaining the return hose to the frame.
13. Remove the retaining clip retaining the return line to the high pressure line. The clip will be reused.
14. Remove the power steering return hose (4) from the steering gear (3).
15. Remove the power steering return hose (4) from the vehicle.

Notice: The inlet and outlet hoses must not be twisted during installation. Do not bend or distort the inlet or outlet hoses to make installation easier. Failure to follow these procedures could result in component damage.

16. Install the new power steering return hose (4) P/N 22717000 to the vehicle.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

17. Install the power steering return hose to the steering gear. DO NOT tighten at this time.
18. Install the power steering return hose retainer fastener (5).

Tighten

•	Tighten the fastener to 13 N·m (10 lb ft).

•	Tighten the return line fitting to 27 N·m (20 lb ft).

19. Install the retaining clip attaching the two power steering lines together. If a clip was not present during removal, install the appropriate clip. See the Parts Table below.
20. Install the right rear cradle fasteners.

Tighten
Tighten the bolts to 110 N·m (71 lb ft).

21. Remove the adjustable jack stand from under the engine cradle.
22. Install the exhaust pipe to the manifold.

Tighten
Tighten the bolts to 45 N·m(33 lb ft).

23. Install the exhaust hangers to the exhaust system.
24. Remove the adjustable jack stand from under the vehicle.
25. Lower the vehicle.
26. Reinstall the fluid restrictor in the pump return line nipple. If a fluid restrictor was not present during removal, install a fluid restrictor, P/N 22592200, in the pump return line nipple.
27. Install the power steering return hose and the clamp to the power steering pump.
28. Install the resonator and duct assembly.
29. Bleed the power steering system. Refer to Bleeding the Power Steering System . Refer to SI Document ID #487449.
30. Remove the fender covers. Close the hood and road test the vehicle.

Parts are expected to be available from GMSPO on July 7, 2003.

For vehicles repaired under warranty, use: