A/T - Service Parts & Unit Repair Information
SUBJECT THM 440-T4 TRANSAXLE SERVICE PARTS & NUMBER: 85-T-28
UNIT REPAIR INFORMATION
DATE: May 14, 1985
MODELS/YEARS 1985 NINETY-EIGHT & 1984-85 SECTION: 7A
CUTLASS CIERA
Hydra-matic is releasing eight new 1985-1/2 THM 440-T4 models to replace the 1985 models as indicated in the chart below. The 1985-1/2 models have a redesigned control valve assembly with a new 3-2 line control valve that makes the 3-2 downshift more responsive to throttle position. The oil passages in the control valve assembly, channel plate, spacer plate, and gaskets have also changed.
1985-85-1/2 MODEL IDENTIFICATION (ALL GM)
1985 MODEL replaced by 1985-1/2 MODEL
AC .................................................................................. AF
AY ................................................................................. AM
BC ................................................................................. BR
BU ................................................................................. BV
BX ................................................................................. BW
CP ................................................................................. CM
CW ................................................................................ CN
HT ................................................................................. HJ
FIGURE 1 - THM 440-T4 TRANSMISSION NAMEPLATE WARREN, MICHIGAN:
SERVICE PARTS INFORMATION
The 1985-1/2 model control valve assembly, spacer plate, and gaskets will not service the 1985 model Until 1985-1/2 model part number listings are available, service replacement parts can be ordered through WDDGM by description (part name). Refer to Figure 1 for correct transaxle model identification information.
FIGURE 2:
FIGURE 3:
UNIT REPAIR INFORMATION
The current chassis service manual describes the 1985 models and will provide enough reference material to cover authorized dealer repairs for 1985-1/2 models. The exception is check ball locations. Refer to Figure 2 for control valve assembly and Figure 3 for channel plate check ball locations for the 1985-1/2 models.
Unit repair information for 1985-1/2 models will be provided in a future bulletin.