A/T - 3T40 Pedal Buzz Under Light Throttle
BULLETIN NO.: 9073T40-11ACORP.REF.NO.: 077126R
DATE: Feb., 1991
TRANSAXLE APPLICATIONS:
1990, 1991 HYDRA-MATIC 3T40
TRANSAXLE MODELS:
KDC, KKC, KNC, KXC,
LJC, LKC, LLC
SUBJECT:
Pedal Buzz at Zero to Light Throttle in Forward Gear Ranges (New Spacer Plate)
VEHICLE APPLICATIONS:
N and W Cars Equipped With 2.3L Engines
J and L Cars Equipped With 3.1L Engines
THIS BULLETIN HAS BEEN REVISED TO INCLUDE SERIAL NUMBER INFORMATION STATED UNDER SECTION "DATE OF PRODUCTION CHANGE". PART NUMBERS HAVE BEEN UPDATED.
BULLETIN COVERS:
A new Spacer Plate 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 instable operation of the 1-2 accumulator valve.
DATE OF PRODUCT CHANGE:
This new Spacer Plate will go 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 built after July 30, 1990 (Julian Date 211) are also affected.
SERVICE ACTION
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.
Package Description Part Number and Transaxle Model
Spacer Plate 8678035 - KDC
Spacer Plate 8678489 - KKC
Spacer Plate 8678488 - KNC
Spacer Plate 8678038 - KXC (1991 only)
Spacer Plate 8678163 - LJC
Spacer Plate 8678164 - LKC
Spacer Plate 8678164 - LLC
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 Unite Repair Section of your service manual.