A/T - Intermittent 2ND Gear Start in D2 When Cold
NUMBER: 93-T-35CORP.REF.NO: 277151
DATE: January 1993
SECTION: 7
SUBJECT:
PRODUCT INFORMATION--POSSIBLE INTERMITTENT SECOND GEAR START IN D2 WHEN COLD
MODELS/YEARS:
1990-91 CUTLASS CALAIS, 1992-93 ACHIEVA,
1990-93 CUTLASS CIERA, CUTLASS SUPREME
AND SILHOUETTE W/3T40 TRANSAXLE
CONDITION:
Some 1990-93 models wfth the HYDRA-MATIC 3T40 transaxles may intermittently start out in second gear when the gear selector is in the intermediate (D2) range, and ambient temperature is low.
CAUSE:
A pressure calibration change was made during the 1990 Model Year to enhance transaxle performance during heavy throttle operation in the intermediate (D2) range. At low ambient temperatures, transaxle fluid viscosity increases and may not exhaust quickly enough from the governor circuit to return the 1-2 shift valve to the downshifted position. This results in a second gear start.
CORRECTION:
No correction is necessary or available for this condition. As the transaxle warms up, fluid viscosity decreases and no longer affects the normal operation of the 1-2 shift valve. This condition does not create any durability concerns.