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Pedals - Buzz on Light Throttle Application

90chevy27
Number: 91-61-7A

Section: 7A

Date: August 1990

Corp. Bulletin No.: 077126
Subject: PEDAL BUZZ AT ZERO TO LIGHT THROTTLE IN FORWARD GEAR RANGES


Model and Year: 1990-91 CAVALIER, CORSICA, BERETTA WITH 3.1L (VIN CODE T) ENGINE
TO: ALL CHEVROLET DEALERS

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 will go into production in all "K" and "U" model HYDRA-MATIC 3T40 transaxles on July 30, 1990 (Julian Date 211).

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.