Chevrolet Silverado / GMC Sierra. Manual - part 984
2. Position the transmission case so that the valve body face of the transmission case is facing
up.
Fig. 482: Manual Valve And Pin
Courtesy of GENERAL MOTORS CORP.
3. Align the manual valve pin (3) with the manual selector valve (2).
4. Rotate the manual valve pin (3) until the pin can be installed into the manual selector valve.
5. Install the manual valve pin (3) into the manual selector valve (2).
6. Install the manual selector valve into shift valve body (1).
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado
Fig. 483: Detent Lever/IMS Assembly
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: Do not drop the manual valve when removing or installing the
control valve assembly onto or from the transmission case.
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado
7. Rotate the detent lever/internal mode switch (IMS) assembly to the fullest counter-
clockwise position.
8. Align the control valve assembly with the transmission case while installing the manual
valve pin (2) into the detent lever/IMS assembly (1).
Fig. 484: Control Valve Body Assembly
Courtesy of GENERAL MOTORS CORP.
9. Align 2 control valve assembly locating pins (1) with the locating pin holes in the
transmission case.
10. Install the control valve body assembly (2) onto the transmission case.
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado
Fig. 485: Park Pawl Cam Guide Hole
Courtesy of GENERAL MOTORS CORP.
11. Remove the lint-free cloth (1) from the park pawl cam guide hole.
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado