PROM - Shudder or Vibration At Low Speeds

91oldsmobile05

NUMBER: 92-T-08

CORP.REF.NO: 136506R

DATE: October 1991

SECTION: 6E2, 7A


SUBJECT: SHUDDER OR VIBRATION AT LOW SPEEDS
- INSTALL NEW PROM


MODELS/YEARS: 1990-92 SILHOUETTE
WITH 3.1L (VIN D) ENGINE


THIS BULLETIN CANCELS AND SUPERSEDES DEALER TECHNICAL BULLETIN 90-T-202 WHICH SHOULD BE DISCARDED.

CONDITION: Some owners of 1990-92 Silhouette vans 3.1L (VIN D) engine may comment of a shudder or vibration at low speeds.

CAUSE: This condition may be caused by the transmission converter clutch being engaged at 23 MPH.

CORRECTION: If normal diagnostic procedures shown in your Service Manual (Section 6E2-B-3) do not correct this condition, a new PROM with a "TCC" ([1][2]torque converter clutch) engagement speed of 35 MPH is available. The part numbers are as follows:

Emission PROM Scanner Broadcast
System Package No. I.D. Code

1990 Vehicles
California 16163425 3431 AYAC
Federal 16163426 3441 AYAD

1991-92 Vehicles
California 16164894 4911 AYHP
Federal 16164893 4901 AYHN

NOTE: This correction will have no impact on performance above 35 MPH.

Parts are currently available from GMSPO.

WARRANTY INFORMATION:
Labor Operation Number: T0500
Labor Time: 0.7 hour
Trouble Code: 92