A/T - Creeps In Neutral/Binds In Reverse/Click/Whine
Bulletin No.: 06-07-30-024Date: September 14, 2006
INFORMATION
Subject:
Information for Diagnosing and Servicing Customer Concerns of Vehicle Creeping Forward in Neutral, Binding in Reverse, and/or Clicking or Whining in All Forward Gears After Transaxle Service
Models:
1991-2002 Saturn S-Series
with Automatic Transaxle (RPO MP6, MP7)
Supercede:
This bulletin is being revised to combine information from two previous bulletins and update the model years. Please discard Corporate Bulletins 91-T-37A and 96-T-04.
The purpose of this bulletin is to assist dealers in diagnosing post-service concerns with MP6 and MP7 automatic transaxles. After servicing an automatic transaxle in which the 1st clutch housing assembly has been removed, a condition may be observed in which the vehicle creeps forward in neutral and binds in reverse. The transaxle may also click or whine in all forward gears with the clicking and whining increasing in frequency with vehicle speed. The noise may be present during acceleration, deceleration and coast conditions.
These conditions may be caused by one of the following:
The 1st gear thrust washer tangs, P/N 21001619, may not be properly aligned with the slots in the 1st clutch housing assembly. A damaged or misaligned 1st gear thrust washer will affect input shaft clearances, which may lead to the condition(s) above.
Any gear and hub assembly may be installed into the clutch pack without all clutch plates engaged, which may lead to the condition(s) above.
To diagnose and correct these conditions, follow the procedures in this bulletin.
Diagnosis and Service Procedures
Diagnosis
Engage the park pawl.
Rotate the input shaft by turning the 1st clutch housing in both directions. The clutch housing should turn freely in both directions.
If the input shaft turns freely in only one direction, the 1st clutch is binding. Disassemble the 1st gear and clutch assembly and follow the service procedure in this bulletin.
If the input shaft will not turn freely in either direction, the 2nd, 3rd or 4th clutch is binding. Refer to the proper repair procedure in the appropriate model year Automatic Transaxle Service Manual or SI.
Inspect the 1st drive gear assembly for a damaged or misaligned 1st gear thrust washer. (Inspect for damage to the 1st gear thrust bearings and the 1st clutch return spring retainer.) If damage exists, the damaged component(s) will need to be replaced. To insure proper assembly of the 1st gear thrust washer in the 1st drive gear assembly, follow the service procedure in this bulletin.
The following procedure is included in the second edition 1996 Saturn S-Series Automatic Transaxle Service Manual.
Service Procedure
Remove and disassemble the 1st gear and clutch assembly. Refer to the appropriate model year Automatic Transaxle Service Manual or SI.
Lay the 1st clutch housing on a flat surface.
Make sure the tabs on the 1st gear thrust washer line up with the slots on the 1st clutch housing assembly hub or damage to the 1st gear thrust washer will occur.
Apply a generous amount of petroleum jelly to hold the 1st gear thrust washer in place and install the 1st gear thrust washer on the 1st clutch housing assembly hub.
The chamfer side goes toward the clutch housing and flat side goes toward the 1st gear.
Install the thrust bearing with the rollers (down) toward the 1st gear thrust washer.
Install the 1st clutch and the clutch (needle) bearing.
Install the 1st drive gear and hub assembly into the 1st clutch housing assembly by twisting the gear to align the gear hub with the clutch tangs.
When installing the 1st drive gear and hub assembly into the clutch pack, rotate the gear and hub assembly back and forth to align the clutch plates. If you are not sure that all of the clutch plates have been engaged, lift the gear out of the clutch housing and verify that all clutch tangs are aligned.
Install the 1st gear thrust washer, P/N 21001619.
Hold the 1st gear and clutch assembly together and install the assembly on the input shaft.
If the assembly is not held together, the gear hub may slide out of the clutch housing, which may allow the 1st gear thrust washer to move out of location or allow the clutch plates to be pinched when the input shaft nut is tightened.
Install the 1st gear and hub assembly and the 1st clutch housing assembly on the input shaft.
After the input and output shaft nuts have been installed, verify proper orientation.
Engage the park pawl.
Rotate the input shaft by turning the 1st clutch housing in both directions. The clutch housing should turn freely in both directions.
If the input shaft turns freely in only one direction, the 1st clutch is binding. Disassemble the 1st gear and clutch assembly and follow the steps in this bulletin.
If the input shaft will not turn freely in either direction, the 2nd, 3rd or 4th clutch is binding. Refer to the proper repair procedure in the appropriate model year Transaxle Service Manual or SI.
If the input shaft turns freely in both directions, refer to the appropriate model year service manual or SI and complete transaxle assembly.
Parts Information
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