Steering Shudder or Vibration at Low Speed (Replace Power Steering Cooler Line)

Some customers may comment on a shudder/vibration condition while steering under low speed or stationary conditions, such as parking lot maneuvers. A low frequency vibration may be felt in the steering wheel and body of the vehicle. In addition, this vibration may be audible in the passenger compartment. This vibration will only occur while the steering wheel is being rotated.

This shudder may be caused by a mechanical vibration of the steering rack, tie rods and tires which is reinforced by hydraulic pressure in the power steering system.

Replace the power steering cooler line with a shortened and relocated cooler line.

Important: The power steering cooler line referenced in this bulletin should only be installed to correct vehicles which exhibit the above shudder/vibration condition. The original equipment power steering cooler line, as shown in the GM Parts Catalog, should be used as a replacement for any other concern.

Procedure

1. Open the hood and apply fender covers.
2. Siphon the power steering fluid from the power steering reservoir.
3. Suitably support and raise the vehicle.
4. Remove the power steering pressure line (lower line) from the steering gear and reposition to gain access to the power steering cooler line.
5. Remove the power steering cooler line at the steering gear (upper line).
6. Remove the constant tension clamp at the power steering reservoir and remove the hose of the cooler from the nipple.
7. Disconnect the power steering cooler from the retainers along the right side cradle member and the retainer under the front air deflector.
8. Remove the cooler line from the vehicle and discard.

Important: The revised power steering cooler line is of a substantially different shape than the original cooler line.




9. Install the revised power steering cooler line to the vehicle. The new cooler line occupies the triangular space between the right side of the cradle, the transaxle pan and the engine oil pan. Refer to the figure for proper positioning.
10. Route the metal line between the cradle crossmember and the rear of the transaxle housing. The cooler line will connect to the upper fitting of the steering gear. The black solid arrow indicates the cooler line attachment point.

Tighten
Tighten the power steering cooler line (gear end) to 27N·m (20 lb ft).

11. Connect the power steering pressure line to the steering gear (lower line).

Tighten
Tighten the power steering pressure line to 27N·m (20 lb ft).

12. Connect the power steering cooler (pump side) to the power steering reservoir with the included constant tension clamp.
13. Secure the line by snapping into the existing cradle mounted retainers. Install the bolt into the metal retaining clip on the new line.

Important: If the bolt should strip, locally obtain a larger self-tapping bolt and re-secure.

14. Lower the vehicle.
15. Refill the power steering reservoir with the new power steering fluid. Bleed the system as outlined in the Steering section of the Service Manual.
16. Remove the fender covers and close the hood.

Parts are currently available from GMSPO.

For vehicles repaired under warranty, use: