Pedals - Buzz At Light Throttle

Number: 91-225-7A


Section: 7A


Date: March 1991


Corporate Bulletin No.: 077126R


Subject: PEDAL BUZZ AT ZERO TO LIGHT THROTTLE IN FORWARD GEAR RANGES


Model and Year: 1990-91 CAVALIER, CORSICA, BERETTA WITH 3.1L ENGINE AND 3T40 AUTOMATIC TRANSMISSION


THIS BULLETIN CANCELS AND SUPERCEDES DEALER SERVICE BULLETIN NO. 91-61-7A. SERIAL NUMBER INFORMATION UNDER SECTION "DATE OF PRODUCTION CHANGE" HAS BEEN INCLUDED AND PART NUMBERS UPDATED. ALL COPIES OF 91- 61-7A SHOULD BE DISCARDED.

BULLETIN COVERS:


A new Spacer Plate (20) with a smaller 1-2 accumulator orifice which will reduce the potential for pedal buzz. This pedal buzz is noticeable at zero to light throttle in forward gear ranges caused by unstable operation of the 1-2 accumulator valve.

DATE OF PRODUCTION CHANGE:


This new Spacer Plate went into production in all "K" and "L" model HYDRA-MATIC 3T40 transaxles for the 1991 model year on July 30, 1990 (Julian Date 211).


NOTE: 1991 KKC model transaxles with serial numbers built between 1011 - 1830 and built after July 30, 1990 (Julian Date 211) are also affected.

SERVICE PROCEDURE:

To service any HYDRA-MATIC 3T40 for a pedal buzz condition, replace the (existing) spacer plate with a new spacer plate which contains the smaller 1-2 accumulator orifice.

SERVICE PARTS INFORMATION:






Refer to the following part numbers whenever ordering this new spacer plate.


Parts are currently available from GMSPO.


SERVICE MANUAL REFERENCE:


Whenever service to the Spacer Plate or valve body assembly is necessary, refer to the HYDRA-MATIC 3T40 Unit Repair Section of your service manual.