A/T - Intermittent 2ND Gear Start in D2 When Cold
Bulletin Number: 93-7-10Reference Number: 277151
Publish Date: 12/92
Subject:
PRODUCT INFORMATION-POSSIBLE INTERMITTENT SECOND GEAR START IN D2 WHEN COLD
Models Affected:
1990-93 6000, SUNBIRD, GRAND AM, GRAND PRIX, LEMANS AND TRANS SPORT MODELS W/3T40 TRANS
TRANSMISSION APPLICATIONS:
1990-93 HYDRA-MATIC 3T40 (RPO MD9)
TRANSMISSION MODELS:
ALL
CONDITION:
Some 1990-93 vehicles with 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 (D21 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.