G5 L4-2.2L (2007)
Output Shaft: All Technical Service Bulletins
M/T - Growling/Grinding Noise in 3rd/4th Gear
Bulletin No.: 07-07-29-001A
Date: April 16, 2007
TECHNICAL
Subject:
MG3, M86 Manual Transaxle Grinding or Growling Noise in 3rd or 4th Gear, Excessive Engagement or Disengagement Effort While Shifting into 5th
or Reverse Gear, Will Not Shift into Either 5th or Reverse Gear (Replace Complete Output Shaft Assembly)
Models:
2005-2007 Chevrolet Cobalt
2006-2007 Chevrolet HHR
2005-2006 Pontiac Pursuit (Canada Only)
2007 Pontiac G5
2003-2007 Saturn ION, VUE
with Getrag(TM) 5-Speed Manual Transaxle (RPOs MG3, M86)
Supercede:
This bulletin is being updated to add additional information on 5th or reverse gear in the Subject, Condition and Cause sections of this bulletin. Please
discard Corporate Bulletin Number 07-07-29-001 (Section 07 - Transmission/Transaxle - Manual Transmission).
Condition
Some customers may comment on any or all of the following conditions:
A grinding or growling noise in 3rd or 4th gear.
Excessive engagement/disengagement effort while shifting into 5th or reverse gear.
The vehicle will not shift into either 5th or reverse gear.
Cause
Diagnosis of the concern will lead the technician to replace the 5th/reverse gear synchronizer assembly and/or the 5th/reverse gear blocking rings on the
output shaft of the transaxle to correct the condition. In order to access either the synchronizer assembly, the blocking rings, or any other components on
the output shaft, the 4th gear must first be removed from the output shaft and then reinstalled after parts have been replaced.
The Service Manual procedure for output shaft assembly states that the 4th gear will install very tight. Some dealers have been unsuccessful in achieving
the press loads required to completely seat the 4th gear on the output shaft during re-assembly, resulting in these dealers replacing the entire manual
transaxle assembly.
Correction
Some technicians may have trouble when pressing gears on or off the output shaft of the Getrag(TM) MG3/M86 five-speed manual transaxle. The output
shaft gears are not splined to the output shaft and are a very tight press fit.
If diagnosis leads to replacement of any components on the output shaft, dealers should follow published Service Information (SI) procedures and use
the appropriate special tools to correctly re-assemble the output shaft.
Pressing Output Shaft Gears
When pressing these gears on or off of the output shaft, care needs to be taken to ensure that the shaft is not nicked or have any burrs on it. (The shaft
and gear need to be free of dirt or debris). Extreme care should be taken not to bind or cock the gear on the shaft. If this happens, press the gear back off
the shaft and start over.
Press loads can reach 2-3 tons on the 4th fixed gear and 12-17 tons on the 3rd fixed gear (both located on the output shaft). The 3rd and 4th speed gears
(on the input shaft) come off with minimal pressure but if trying to remove the 5th fixed gear and the 3rd speed gears at the same time, press loads in
excess of 20 tons will not move the gear. Gears need to be removed and installed one at a time.
If dealers are not able to properly seat the 4th gear on the output shaft, a complete output shaft assembly for MG3 and M86 manual transaxles is being
