Chevrolet Silverado / GMC Sierra. Service manual — part 869

Fig. 101: Identifying Main Transmission Connector
Courtesy of GENERAL MOTORS CORP.

3. Push the main transmission connector (2) outward through hole (1) in the transmission case

until the retaining feet on the connector are near the locked position.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

Fig. 102: Using J 44247 To Seat Transmission Connector
Courtesy of GENERAL MOTORS CORP.

4. Use J 44247 to seat the retaining feet on transmission connector (1). See Special Tools.

5. Install the oil pan and transmission internal oil filter. Refer to Oil Pan Replacement.

6. Connect the external wiring harness to the main transmission connector.

IMPORTANT: The FastLearn, adapt, procedure must be performed. This

can be done in 1 step using a scan tool. If this procedure is
not done, the TCM adaptive values will be at the settings that
it learned for the old components and will be in slow
adaptive mode. Under these conditions, it will take an

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

7. Perform the FastLearn procedure. Refer to FastLearn Procedure.

AUTOMATIC TRANSMISSION FLUID PRESSURE TEST HOLE PLUG REPLACEMENT

Removal Procedure

Fig. 103: View Of Pressure Tap Plug And O-Ring
Courtesy of GENERAL MOTORS CORP.

unacceptably long time for the adaptive values to converge
to levels suitable for the new transmission.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

1. Remove the pressure tap plug (2) and O-ring (1) on the bottom of the converter housing

near the transmission external oil filter.

2. Remove the O-ring from the plug and discard it.

Installation Procedure

Fig. 104: View Of Pressure Tap Plug And O-Ring
Courtesy of GENERAL MOTORS CORP.

1. Install a new O-ring (1) on the pressure tap plug (2).

NOTE:

Refer to Fastener Notice .

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado