Case Extension Install/Final Drive End Play Check

Special Tools

• J 25025-7A  Dial Indicator Post
• J 28585  Snap Ring Remover
• J 8001  Dial Indicator

For equivalent regional tools, refer to Special Tools .

Fig 1: View of Case Extension Seal
Courtesy of GENERAL MOTORS COMPANY
1. Inspect the case to case extension seal (126).
2. Inspect the case extension mating surface for damage.
Fig 2: View Of Case Extension Components
Courtesy of GENERAL MOTORS COMPANY
3. Install the following parts:
   • The selective washer (133)
   • The thrust washer (132)
   • The case extension seal (126)
   • The case extension (134)
Fig 3: Identifying Case Extension Bolts
Courtesy of GENERAL MOTORS COMPANY
4. Apply pip thread sealant GM P/N 12346004 to bolt threads before installation. Install the case extension bolts (128, 129).
5. Hand tighten bolts (128, 129) until case extension (134) is seated onto case.
Fig 4: Measuring End Play Clearance
Courtesy of GENERAL MOTORS COMPANY
CAUTION:

Failure to ensure that proper end play clearance exists, could lead to internal component damage.

6. Install the long J 25025-7A  dial indicator postand the J 8001  dial indicator.
7. Position the dial indicator with the stem contacting the output shaft (112). Set the dial indicator to zero.
8. Insert the J 28585  snap ring removerthrough the vehicle speed sensor bore and lift the speed sensor rotor for measurement. Protect the bore with a piece of wood or a suitable piece of plastic.
9. Proper end play clearance is 0.15-0.65 mm (0.006-0.255 in).
10. Record measured specification and, if necessary, adjust the clearance with the proper thickness selective thrust washer on reassembly. Refer to step 3.
11. Remove the dial indicator set and the post.
Fig 5: Identifying Case Extension Bolts & Studs
Courtesy of GENERAL MOTORS COMPANY
CAUTION:

Refer to Fastener Caution .

12. Install the stud (127).
    • Tighten the bolt (128) and the stud (127) to 50-55 N.m (37-40 lb ft).
    • Tighten the bolt (129) to 20-27 N.m (15-20 lb ft).