A/T Fluid Flow Diagrams - Update
88olds11SUBJECT 1987 SERVICE MANUAL UPDATE OF FLUID FLOW DIAGRAMS 1987 THM 440-T4 (ME9)
1987 CUTLASS CIERA, DELTA 88, NINETY-
MODELS/YEARS EIGHT, TORONADO MODELS EQUIPPED
WITH 440-T4 TRANSAXLE
NUMBER: 87-T-69
CORP. REF. NO.: 777151
DATE: May 1988
SECTION: 7A
FIGURE 1:
BULLETIN COVERS: (Figure 1)
Fluid flow diagrams published in the 440-T4 Hydraulic Diagnosis Section of the 1987 Oldsmobile Chassis Service Manual were not current. Use the corrected diagram in this bulletin to update your service manual. Note the following two changes:
^ Spacer plate hole for the number 14 checkball was added, making the checkball functional (refer to arrow, Figure 1). With this change, line pressure is now boosted by detent fluid at full throttle opening.
^ Modulator circuit no longer feeds the 3-2 coastdown valve directly, and 1-2 servo release circuit was routed to the 3-2 coastdown valve by a crossover pipe between the pump cover and the control valve assembly (refer to dotted line and circle, Figure 1). These changes were part of a package to improve 3-2 shift feel.
SERVICE NOTES:
The spacer plate and checkball location illustrations in the 1987 service manual are correct.