Subject: | NVG 126/226 Transfer Case Grating/Grinding Noise When 4WD is Engaged, Service 4WD Lamp On, DTC C0327 Set (Replace Clutch Pressure Plate Bearing Assembly and Clutch Lever) |
Models: | 2004-2007 Buick Rainier |
2002-2008 Chevrolet TrailBlazer Models |
2002-2008 GMC Envoy Models |
2002-2004 Oldsmobile Bravada |
2005-2008 Saab 9-7X |
with Four-Wheel Drive or All-Wheel Drive |
and Active All-Wheel Drive (RPO NP4) or Active Two-Speed (NP8) Transfer Case |
Built Prior to September 18, 2007 (NVG 126) or September 21, 2007 (NVG 226) |
This bulletin is being revised to update the correction information to include a procedure to reindex the transfer case encoder motor (actuator). This procedure is being provided to help reduce unnecessary warranty expenses. Please discard Corporate Bulletin Number 08-04-21-001A (Section 04 - Transmission/Transaxle).
Some customers may comment on a grinding type noise in the transfer case when 4WD is engaged in either AUTO or 4WD mode. This noise may also be accompanied by the SERVICE 4WD lamp being illuminated and DTC C0327 set.
This condition is more prevalent on vehicles where 4WD is continuously used.
This noise may be caused by a faulty clutch pressure plate bearing.
Do This | Don't Do This |
---|---|
Replace the clutch pressure plate bearing assembly and clutch lever. Perform the transfer case encoder motor (actuator) indexing procedure. | Do not replace the transfer case encoder motor (actuator). |
A more robust clutch pressure plate bearing, inner plate and clutch lever has been released for service. Replace the clutch pressure plate bearing, inner plate and clutch lever. Refer to the Transfer Case Disassemble and Transfer Case Assemble procedures in SI. Former and new parts should not be intermixed during transfer case overhaul and they are to be used in sets only.
DO NOT replace the transfer case assembly unless extensive internal damage has occurred.
Important: When the clutch pressure plate bearing fails, it causes the clutch lever to over-travel, allowing the transfer case encoder motor (actuator) to rotate to an invalid position. Engineering has developed a tool and procedure to reindex the transfer case encoder motor (actuator) so it can be reused. Use the specific procedure listed below.
• | (1) EL-49741 9 Volt Encoder Motor (Actuator) Jumper Harness (Tool can be obtained from SPX/Kent Moore by calling 1-800-GM-TOOLS (1-800-468-6657)) |
• | (2) J-35616-5 Terminal Test Adapter (Test Probe) |
• | (1) 9 Volt Battery (obtain locally) |
Note: If available, another option is to rotate the encoder motor (actuator) shaft until a shipping plug from a new encoder motor (actuator) can be installed.
• | (1) EL-49741 9 Volt Encoder Motor (Actuator) Jumper Harness (Tool can be obtained from SPX/Kent Moore by calling 1-800-GM-TOOLS (1-800-468-6657)) |
• | (4) J-35616-5 Terminal Test Adapter (Test Probe) |
• | (2) 9 Volt Battery (obtain locally) |
Note: If available, another option is to rotate the encoder motor (actuator) shaft until a shipping plug from a new encoder motor (actuator) can be installed.
Part Number | Description |
---|---|
19178973 | Clutch Pressure Plate Bearing Assembly with Inner Plate |
19178970 | Clutch Lever |
24242560 (NVG 126) | Transfer Case |
24242561 (NVG 226) | Transfer Case |
For warranty claims, submit batteries as parts.
For vehicles repaired under warranty, use the appropriate labor operation for the repair performed:
Labor Operation | Description | Labor Time |
---|---|---|
K4400* | Transfer Case Assembly - R&R | Use Published Labor Operation Time |
K4410 | Transfer Case Assembly - Replace | Use Published Labor Operation Time |
* Includes time to perform the transfer case encoder motor (actuator) indexing procedure. |
For vehicles repaired under warranty, use:
Labor Operation | Description | Failed Object | Fault/Reason Code | Location Code | Warranty Type | Repair/Action Code | Labor Time |
---|---|---|---|---|---|---|---|
4411001* | Transfer Case Assembly - R&R (Engine Code S) | 44100 | 47 | 0 | 01 | 01 | Use Published Labor Operation Time |
4411007* | Transfer Case Assembly - R&R (Engine Code M) | 44100 | 47 | 0 | 01 | 01 | Use Published Labor Operation Time |
4411009 | Transfer Case Assembly - Replace (Engine Code S) | 44100 | 47 | 0 | 01 | 01 | Use Published Labor Operation Time |
4411010 | Transfer Case Assembly - Replace (Engine Code M) | 44100 | 47 | 0 | 01 | 01 | Use Published Labor Operation Time |
* * Includes time to perform the transfer case encoder motor (actuator) indexing procedure. |