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A/T - 3rd-2nd Gear Downshift Bump

Bulletin 85-7440-11

Date Jan. '86

Ref. No. 85-317-7440
SUBJECT: 3-2 DOWNSHIFT BUMP

MODELS AFFECTED: 1985 CENTURYS AND ELECTRAS WITH 3.8L V-6 ENGINE AND 440-T4 TRANSAXLE

FIGURE 1 - THM 440-T4 TRANSAXLE I.D. INFORMATION:




Some 1985 THM 440-T4 "BA" and "BC" model transaxles (refer to Figure 1), may exhibit a 3-2 downshift bump. The condition may be most prevalent during a part-throttle downshift with the air conditioner operating.
When servicing any 1985 THM 440-T4 "BA" and "BC" model for a 3-2 downshift bump, order and install service package part number 8646953.

Service package part number 8646953 contains one each of the following:

3-2 Control Valve Spring Instruction Sheet

FIGURE 2 - CONTROL VALVE ASSEMBLY:




Refer to Figure 2 of this bulletin and the appropriate chassis service manual for proper installation procedures.

NOTICE: This correction does not apply to 1985-1/2 440-T4 models or to vehicles equipped with 3.0L engines. Refer to chassis service manual 440-T4 diagnosis for shift conditions on other than "BA" or "BC" models.