| Subject: | Revised Liftgate Lock Cylinder Replacement | 
| Models: | 2004-2006 Buick Rainier Models | 
 | 2002-2006 Chevrolet TrailBlazer Models | 
 | 2002-2006 GMC Envoy Models | 
 
This bulletin is being issued to revise the Lock Cylinder Replacement - Liftgate procedure in the Body Rear End sub-section of the Service Manual. Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this Service Manual, please make a reference to this bulletin on the affected page.
When replacing the liftgate lock cylinder, removal of the rear window wiper motor, if equipped, is required.
Lock Cylinder Replacement - Liftgate
Removal Procedure
-  Remove the rear wiper motor. Refer to  Wiper Motor Replacement - Rear.
 
- Remove the lock rod from the lock cylinder. 
 
- Remove the C clip from the groove in the lock cylinder. 
 
- Remove the lock cylinder from the liftgate. 
 
Installation Procedure
-  Install the lock cylinder to the liftgate. 
 
- Install the C clip to the groove in the lock cylinder.
 
- Install the lock rod to the lock cylinder. 
 
- Install the rear wiper motor. Refer to  Wiper Motor Replacement -- Rear.