POWER STEERING SHUDDER (INSTALL HIGH EXPANSION HOSE)

SUBJECT: POWER STEERING SHUDDER (INSTALL A "TUNED" OR HIGH EXPANSION HOSE)

MODELS AFFECTED: 1989-91 CUTLASS CALAIS

THIS BULLETIN CANCELS ND SUPERSEDES DEALER TECHNICAL BULLETINS 90-T-44A AND 90-T-44B WHICH SHOULD BE DISCARDED.

MODELS/YEARS AFFECTED: 1989-91 W/2.5L (VIN U) Engine 1990 W/2.3L (VIN D OR A) engine 1989-90 W/ 3300 (VIN N) engine

CONDITION:

----------- Customers may comment about a shudder, moan or vibration that occurs when turning the steering wheel under the following conditions:

- Vehicle stopped with brake applied (or moving very slowly) - Vehicle in gear - Engine at idle speed

The shudder or moan may occur during parking maneuvers or other situations when the steering wheel is turned while the vehicle is stopped or moving very slowly. It is also sensitive to steering wheel rotational speed as well as engine speed. The shudder is commonly more severe during hot ambient temperatures.

CAUSE:

------ A combination of steering gear valve instability and/or engine firing pulses generating a disturbance that is transmitted through the body structure.

CORRECTION:

----------- Install a "tuned" power steering return hose and/or high expansion pressure hose between the steering pump and gear.

1990 Cutlass Calais w/2.3L (VIN D or A) engine

Starting with the following VIN breakpoints 1990 vehicles are equipped with a "tuned" return hose which should reduce or eliminate the shudder condition.

"TUNED" RETURN HOSE

Lansing LM017241

Starting with the vehicle number LM717359, 1990 vehicles are also equipped with a "tuned" return hose which should reduce or eliminate the shudder condition.

NEW PRESSURE HOSE

Starting with the vehicle number LM717359, 1990 Vehicles are also equipped with a new high expansion pressure hose which further reduces the sudder condition.

Vehicles built BEFORE the above listed "TUNED RETURN HOSE" breakpoint, and the shudder condition, may be repaired by installing a "tuned" return hose, P/N 26023904. In a very limited number of cases, the tuned return hose may not completely eliminate the shudder condition. In these cases, the condition may be repaired by installing a new high expansion pressure hose, P/N 26024244 (and removal of the clip from the power steering pump).

Vehicle built ON OR FOLLOWING the above listed "TUNED RETURN HOSE" VIN breakpoint, but before the above listed "NEW PRESSURE HOSE" VIN breakpoint, are equipped with tuned return hoses, but are not equipped with new high expansion pressure hoses. For vehicles in this range that still exhibit some power steering shudder, the condition may be repaired by installing a new high expansion hose, P/N 26024244 (and removal of the clip from the power steering pump).

1989-90 with 3300 (VIN N) Engine

Starting with the vehicle number LM778565, vehicles are equipped with a new high expansion pressure hose which corrects this condition.

In vehicles built before these VIN breakpoints, this condition may be repaired by installing a new high expansion pressure hose, P/N 26026183.

1990-91 with 2.5L (VIN U) Engine ---------------------------------- Starting with the vehicle number MM016754, 1991 vehicles are being built with a new "tuned" return hose which corrects this condition.

In vehicles built before these VIN breakpoints, this condition may be repaired by installing a new "tuned" return hose, P/N 26027298.

Vehicles with tuned return hoses that still exhibit steering shudder, install a high expansion pressure hose, P/N 26027234.

Note: If the above hoses do not repair the shudder condition, please contact Technical Assistance.

Parts are currently available from GMSPO.

Engine VIN Model Model Year Carline Engine Code Years Hose Type P/N VIN Breakpt Note ------- ------ ------ ------ ----------- --------- ------------ ---- N 2.3L D or 1990 Tuned Return 26023904 1990- 2 LD2/LG0 A LM717359 ----------------------------------------------------------------------------- N 2.3L D or 1990 High 26024244 1990 1,2 LD2/LG0 A Expansion LM744715 ----------------------------------------------------------------------------- N 3.3L N 1989-90 High 26026183 1990 2 LG7 Expansion LM778565 ----------------------------------------------------------------------------- N 2.5L U 1989-91 Tuned 26027298 1991 2 L68 Return MM016754 ----------------------------------------------------------------------------- N 2.5L U 1989-91 High 26027234 SERVICE 3 L68 Expansion ONLY

NOTE: 1. Use Return Hose P/N 26023904 before installing this new pressure hose. Remove P/S pump hose clip. 2. Vehicles built after this breakpoint already contain this hose. 3. Use return hose P/N 26027298 before installing this new pressure hose. IF THE HOSES LISTED DO NOT WORK, PLEASE CONTACT TECHNICAL ASSISTANCE.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.