Service Procedure
IMPORTANT:The labor time allowance listed in this recall is different than that currently published in the labor time guide for performing the same operation. In the near future, the labor time guide will be updated with this new information.
Clean Neutral Test
Caution:
Please use the parking brake when the vehicle is parked or left unattended.
1. Position the vehicle on a level surface, engine on, and apply the service brake.
IMPORTANT:
ENSURE FRONT AND REAR OF VEHICLE ARE CLEAR OF BUILDINGS, OTHER VEHICLES AND PERSONNEL.
2. Place the transmission in neutral and shift the transfer case to neutral (Rotate and hold the transfer case shift selector switch past 4Lo for ten seconds. An "N" indicator light on the switch will indicate the shift. The vehicle speed must be below 3 mph, (5 kph)).
^ Shift the transmission to Reverse, then to Neutral and then to Drive; release the service brake, but keep the transfer case in neutral.
^ While in Drive VERY LIGHTLY press the throttle, then release the throttle.
^ Shift the transmission to neutral and repeat light throttle, then release the throttle.
^ Shift the transmission to reverse and repeat light throttle.
^ If the vehicle does not move under power (depending on the testing surface, the vehicle could still roll because the transfer case is in neutral) and makes no noise (e.g. ratcheting noise, gear face contact noise) in the transfer case beyond noises that would be expected from the transmission or transfer case as detected at the driver's location (a clean neutral), go to Active Transfer Case Control Module Reprogramming and update with calibration # 12575794.
^ If the vehicle does move under power or makes a noise (e.g. ratcheting noise, gear face contact noise), replace the transfer case. The transfer case must be ordered through the Technical Assistance Center (TAC) at 1-877446-8227. For Canadian dealers, call 1-800-263-7740 (English) or 1-800-263-7960 (French). Go to Transfer Case Replacement.
Transfer Case Replacement
Removal Procedure
1. Raise the vehicle.
2. Remove the fuel tank shield retaining bolts.
3. Remove the fuel tank shield.
4. Remove the rear propeller shaft.
^ Reference mark the propeller shaft to the rear axle pinion yoke.
^ Remove the bolts and the yoke retainers from the rear axle pinion yoke.
^ Disconnect the propeller shaft from the rear axle pinion yoke.
^ Slide the propeller shaft rearward in order to disconnect the propeller shaft from the transfer case.
5. Drain the transfer case.
^ Remove the drain plug and drain fluid into a suitable container.
^ Install the drain plug. Tighten the plug to 34 Nm (25 lb ft).
6. Remove the front propeller shaft.
^ Reference mark the propeller shaft to the front axle pinion yoke.
^ Remove the bolts and the yoke retainers from the front axle pinion yoke.
^ Disconnect the propeller shaft from the front axle pinion yoke.
^ Remove the propeller shaft from the transfer case.
7. Remove the fuel lines from the retainer.
8. Remove the electrical harness from the retainers.
9. Remove the electrical connector from the speed sensors.
10. Remove the motor/encoder electrical connector.
11. Remove the transfer case wiring harness.
12. Remove the vent hose.
13. Install a transmission jack for the transfer case.
14. Remove the transfer case mounting nuts.
15. Remove the transfer case from the vehicle.
16. Remove the transfer case gasket.
Installation Procedure
Important:
DO NOT use silicone sealant in place or with the transfer case gasket.
1. Replace the transfer case gasket.
2. Install the transfer case in the vehicle.
3. Install the transfer case mounting nuts. Tighten the nuts to 47 Nm (35 lb ft).
4. Remove the transmission jack stand.
5. Install the transfer case speed sensors electrical connectors.
6. Install the vent hose.
7. Install the motor/encoder electrical connector.
8. Install the transfer case harness to the transfer case.
9. Install the transfer case wiring harness to the retainers.
10. Install the fuel lines to the retainer.
11. Install the rear propeller shaft.
^ Install the propeller shaft into the transfer case.
^ Install the propeller shaft to the rear axle pinion yoke. Align the reference marks made during removal.
^ Install the yoke retainers and the bolts. Tighten the bolts to 20 Nm (15 lb ft).
12. Install the front propeller shaft.
^ Install the propeller shaft to the transfer case.
^ Install the propeller shaft to the front axle pinion yoke. Align the reference marks made during removal.
^ Install the yoke retainers and the bolts. Tighten the bolts to 20 Nm (15 lb ft).
13. Install the fuel tank shield.
14. Install the fuel tank shield retaining bolts. Tighten the bolts to 25 Nm (18 lb ft).
15. Lower the vehicle and continue with Active Transfer Case Control Module reprogramming.
Active Transfer Case Control Module Reprogramming
1. Reprogram the transfer case control module with calibration P/N 12575794.
A. Connect the scan tool to the vehicle.
B. Power-up the scan tool and select the Service Programming feature.
C. Select the appropriate vehicle.
D. Press the Request Info button on the scan tool.
E. Connect the scan tool to the computer station.
F. Follow the menu select items for reprogramming and provide information as to what device you are programming and whether you are reprogramming or replacing the electronic control unit (ECU).
G. Select "vehicle" from the selection menu.
H. Select "ATC Active Transfer Case Module" to program.
I. Select "Normal" for Programming Type.
J. Select the applicable software calibrations.
K. Transfer data file to the scan tool.
L. Position the left side second row seat in order to access the rear fuse block.
M. Remove the No. 6 (Liftgate Module/Driver Seat Module) fuse.
N. Reconnect the scan tool to the vehicle.
0. Turn ON the ignition, with the engine OFF.
P. Select the Service Programming feature on the scan tool.
Q. Press the Program button on the scan tool.
R. Install fuse and reposition the seat.
2. Perform system check by shifting transfer case to all modes of operation.
3. Install the GM Recall Identification Label.