Grand AM L4-121 2.0L (1988)
Band Apply Servo: All Technical Service Bulletins
A/T - No Second Gear
Bulletin Number:
89-7-9
Reference Number:
877149
Publish Date:
11/88
Subject:
NO SECOND GEAR
Models
1988-89 6000, SUNBIRD, GRAND AM,
Affected:
FIERO AND LeMANS EQUIPPED WITH
THM 125C/HYDRA-MATIC 3T40
BULLETIN COVERS:
A No Second Gear condition that may be caused by a rough surface finish on the Intermediate Servo Cover Piston Bore (137). This finish will wear the
lip off the (inner) Intermediate Servo Seal (132), causing a leak in the piston bore. This leak may cause Intermediate Band (606), and Direct Clutch (608
- 617) wear.
SERVICE ACTION:
If a customer comments about a No Second Gear condition in any THM 125C/HYDRA-MATIC 3T40, the Intermediate Band and Direct Clutch
Assembly should be inspected for possible wear. To service this condition on a 1988 or 1989 125C/HYDRA-MATIC 3T40, inspect for a worn inner lip
seal and cover surface machine finish. If the finish is rough, install a new Intermediate Servo Cover and Intermediate Servo oil ring seals (inner and
outer).
SERVICE NOTES:
Do not attempt to sand the intermediate servo cover bore machine finish with Crocus cloth, soft stone or any other smoothing material.
SERVICE PARTS INFORMATION:
When ordering a new Intermediate Servo Cover and Intermediate Servo oil ring seals (inner and outer), refer to the following part list:
Intermediate
Intermediate
Servo Piston and Seals
Servo Cover
.79 Ratio - 8652901
.79 Ratio - 8631702
.71 Ratio - 8652900
.71 Ratio - 8631703
.64 Ratio - 8652911
.64 Ratio - 8631704
Parts are currently available from GMSPO.
SERVICE MANUAL REFERENCE:
When servicing any 125C/HYDRA-MATIC 3T40 refer to the procedures outlined in the Unit Repair Section of your Service Manual.