GM Service Manual Online
For 1990-2009 cars only
Table 1: 1-2-3-4 Clutch Backplate
Table 2: Low and Reverse Clutch Piston Housing Selective Shim
Table 3: Low and Reverse Clutch Steel Plate Minimum Thickness
Table 4: Low and Reverse Clutch Steel Selective Plate

1-2-3-4 Clutch Backplate

Identification

Plate Thickness

Metric

English

2420

11.1-11.9 mm

0.4370-0.4685 in

8521

11.54-12.34 mm

0.4543-0.4858 in

8522

11.98-12.78 mm

0.4717-0.5031 in

8523

12.43-13.23 mm

0.4894-0.5209 in

8524

12.88-13.68 mm

0.5071-0.5386 in

8525

13.33-14.13 mm

0.5248-0.5563 in

Low and Reverse Clutch Piston Housing Selective Shim

Dimension C

Thickness

Identification

Metric

English

Metric

English

1.008-1.184 mm

0.0397-0.0466 in

0.245-0.295 mm

0.0096-0.0116 in

0 Holes

1.185-1.414 mm

0.0467-0.0557 in

0.475-0.525 mm

0.0187-0.0207 in

1 Hole

1.415-1.644 mm

0.0557-0.0647 in

0.705-0.755 mm

0.0278-0.0297 in

2 Holes

1.645-1.874 mm

0.0648-0.0738 in

0.935-0.985 mm

0.0368-0.0388 in

3 Holes

1.875-2.104 mm

0.0738-0.0828 in

1.165-1.215 mm

0.0459-0.0478 in

4 Holes

2.105-2.334 mm

0.0829-0.0919 in

1.395-1.445 mm

0.0549-0.0569 in

5 Holes

2.335-2.510 mm

0.0919-0.0988 in

1.625-1.675 mm

0.0640-0.0659 in

6 Holes

Low and Reverse Clutch Steel Plate Minimum Thickness

Minimum Thickness

Identification

Metric

English

1.935 mm

0.0762 in

1

2.435 mm

0.0959 in

2

2.935 mm

0.1156 in

3

Low and Reverse Clutch Steel Selective Plate

Dimension C

Identification

Metric

English

35.3-35.86 mm

1.393-1.412 in

1

35.87-36.36 mm

1.413-1.431 in

2

36.37-37.27 mm

1.432-1.467 in

3