Sierra 1500 2WD V6-4.3L (2008)
Valve Body: Service and Repair
Allison - Automatic Transmission
Control Valve Body Replacement
Tools Required
*
J 44247 Internal Wiring Harness Installer
*
J 44257 Main Wiring Harness Connector Remover
Removal Procedure
Caution: Refer to Battery Disconnect Caution .
1. Disconnect the external wiring harness from the transmission main connector. Use J 44257 if the connector is not easily accessible.
2. Remove the oil pan and transmission internal oil filter. Refer to Oil Pan Replacement (See: Fluid Pan/Service and Repair/Allison - Automatic
Transmission) .
Important: The transmission main connector is actually one end of the internal harness that protrudes through the transmission case.
3. Place a 30 mm (1 3/16 in) 12-point deep socket or box-end (2) over the connector (1).
4. Push inward on the socket or wrench to release the retainer feet that attach the connector (1) to the transmission case.
5. Remove the wrench. Push inward on the electrical connector to separate it from the transmission case. This allows the internal wiring harness to
remain with the control valve assembly when removed.
