Chevrolet Silverado / GMC Sierra. Manual - part 945
Fig. 353: Locating Low And Reverse Clutch Backing Plate Inspection Areas
Courtesy of GENERAL MOTORS CORP.
1. Measure the thickness of each low and reverse clutch backing plate (1) at dimension A.
Specification: The low and reverse clutch backing plate minimum thickness is 17.900 mm
IMPORTANT: Perform the following measurements at 3 or more locations.
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado
(0.7047 in).
2. Measure the cone of the low and reverse clutch backing plate (1).
3. Replace the low and reverse clutch backing plate (1) if any cone is present.
INPUT INTERNAL RING GEAR INSPECTION
Fig. 354: Input Internal Ring Gear
Courtesy of GENERAL MOTORS CORP.
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado
1. Inspect the external splines of the input internal ring gear (1) for notching.
2. Replace the ring gear if detectable notching has occurred.
MAIN SHAFT CLEANING AND INSPECTION
Fig. 355: Inspection Areas On Main Shaft
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: Clutch plate movement can cause notching on the external
splines of the input internal ring gear.
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado
1. Inspect the main shaft pilots for damage.
2. Measure the main shaft pilots at dimension A.
Specification: The main shaft pilot minimum outside diameter is 19.987 mm (0.7869 in).
3. Inspect the main shaft journal contact area for damage.
4. Measure the main shaft journal contact area at dimension B.
Specification: The main shaft journal minimum diameter is 36.405 mm (1.4333 in).
INPUT CARRIER ASSEMBLY DISASSEMBLE
IMPORTANT: Replace the main shaft if the specifications are not met.
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado