Chevrolet Silverado / GMC Sierra. Service manual — part 942

Fig. 342: Measuring Thickness Of Clutch Backing Plate
Courtesy of GENERAL MOTORS CORP.

8. Measure the thickness of the 3rd, 5th, and reverse clutch backing plate (1) at dimension C.

Specification: The 3rd, 5th, and reverse clutch backing plate minimum thickness is 15.325
mm (0.6033 in).

9. Measure the distance from the top of the thrust plate (2) to the bottom of the 3rd, 5th, and

2008 Chevrolet Silverado 1500

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

Silverado

reverse clutch plate inner rim at dimension A.

10. Measure the thickness of the 3rd, 5th, and reverse clutch plate inner rim at dimension B.

11. Calculate the thickness of the thrust plate by subtracting Dimension B from Dimension A.

Specification: The thrust plate minimum thickness is 3.000 mm (0.1181 in).

12. Measure the cone of the 3rd, 5th, and reverse clutch backing plate (1).

13. Replace the backing plate if any cone is present.

2-6 CLUTCH PLATE INSPECTION

IMPORTANT: Check the plates for coning on a level surface.

2008 Chevrolet Silverado 1500

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

Silverado

Fig. 343: Measuring Clutch Oil Groove Depth & Fiber Plate Thickness
Courtesy of GENERAL MOTORS CORP.

IMPORTANT:

Perform the following measurements at 3 or more
locations.

Check the plates for coning on a level surface.

Replace any parts not meeting specifications.

2008 Chevrolet Silverado 1500

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

Silverado

1. Measure the thickness of each 2-6 clutch fiber plate (1) at dimension A.

Specification: The 2-6 clutch fiber plate minimum thickness is 2.375 mm (0.0935 in).

2. Measure the oil groove depth of each 2-6 clutch fiber plate (1) at dimension B.

Specification: The 2-6 clutch fiber plate oil groove minimum depth is 0.2 mm (0.0079 in).

Fig. 344: Measuring Cone Of Clutch Fiber Plate
Courtesy of GENERAL MOTORS CORP.

3. Measure the cone of each 2-6 clutch fiber plate (1) at dimension A.

Specification: The 2-6 clutch fiber plate maximum cone is 0.225 mm (0.0089 in).

2008 Chevrolet Silverado 1500

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

Silverado