Transmission Fluid Leak at Rear of Vehicle (Remove Burrs and Replace Inner and Outer Output Shaft Seals)

Some customers may comment on transmission fluid leaking from the rear of the vehicle. This may be the second attempt to repair the leak.

This condition may be caused by transmission fluid leaking through the weep hole on the transmission extension housing. The weep hole is located between the inner and outer seals on the extension housing. An aluminum burr may prevent proper alignment of the inner seal allowing fluid to leak past the inner seal and out the weep hole. Leak may have been misdiagnosed as the outer seal.

Verify that the fluid leak is transmission fluid, not axle fluid. Remove any burrs on the transmission extension housing inner seal surface and replace the inner and outer output shaft seals. Use the procedure and part numbers listed below.

1. Raise and support the vehicle.
2. Remove the tire and wheel assemblies.
3. Install J 33432-A Transverse Spring Compressor to the rear transverse spring and compress the spring.
4. Disconnect the electrical connectors from both wheel speed sensors.
5. Disconnect the electronic suspension control (ESC) position sensor links, if equipped.
6. Disconnect the shock absorber solenoid electrical connectors, if equipped.
7. Remove the brake calipers from the caliper mounting brackets and support aside.
8. Remove the outer tie rod end nuts.
9. Disconnect the outer tie rod end studs from the rear suspension knuckles.
10. Disconnect the park brake cables from the park brake apply levers and brackets.
11. Remove the shock absorber lower mounting bolts from the lower control arms.
12. Remove the bolts securing the upper control arms to the frame.
13. Remove the spindle nuts retaining the rear wheel axle shafts to the hubs.
14. Rotate the suspension knuckles until the axle shafts clear the hubs.
15. Disconnect the wiring harness and brake pipe clip retainers from the rear suspension crossmember.
16. Remove the transaxle mount to rear crossmember nuts.
17. Position an adjustable jack stand under the transmission and support the transmission.
18. Position a transmission jack under the rear suspension crossmember and firmly secure the crossmember to the jack.
19. Remove the rear suspension crossmember mounting nuts.
20. Slowly lower the rear suspension crossmember away from the vehicle frame rails and remove the crossmember.
21. Release and remove the rear wheel axle shafts from the differential.
22. Remove the right and left mufflers.
23. Remove the exhaust pipe hanger bolts.
24. Remove 22 bolts attaching the driveline tunnel closeout panel to the underbody.
25. Drain the transmission fluid. Refer to the Transmission Fluid Replacement procedure in the Manual Transmission sub-section of the Service Manual (SI Document ID #765021).
26. Drain the rear differential fluid. Refer to the Lubricant Change procedure in the Rear Axle sub-section of the Service Manual (SI Document ID #675189).
27. Lower the driveline as necessary.
28. Disconnect the vehicle speed sensor (VSS) electrical connector.
29. Disconnect the wiring harness retainer from the stud at the differential rear cover.
30. Disconnect the wiring harness retainer clip from the top of the differential.
31. Remove the rear differential to transmission nuts and bolts.
32. Lower the driveline and remove the rear differential from the vehicle. Differential must be rotated while removing to clear rear compartment tub.
33. Remove the transmission extension housing to transmission bolts and remove the extension housing from the transmission.
34. Remove the outer and inner output shaft seals from the transmission extension housing. Pry out the seals with a suitable tool.
35. Remove any burrs from the inner seal surface.

Important: Failure to install the inner output shaft seal correctly may cause a leak.

36. Install the inner output shaft seal with the garter spring facing inward, using J 26508 Inner Output Shaft Seal Installer.

Important: Failure to install the outer output shaft seal correctly may cause a leak.

37. Install the outer output shaft seal with the garter spring facing outward, using J 42198 Transmission Rear Seal Installer.
38. Clean the transmission extension housing to transmission mating surfaces.
39. Apply RTV sealant, P/N 12345739 (in Canada, 10953541), to the extension housing surface.
40. Install the transmission extension housing to the transmission.
41. Apply thread sealer, P/N 12346004 (in Canada, 10953480), to the transmission extension housing bolts.
42. Install the transmission extension housing to transmission bolts.

Tighten
Tighten the extension housing bolts to 48 N·m(36 lb ft).

43. Install the rear differential to the transmission.
44. Install the rear differential to the transmission bolts and nuts.

Tighten
Tighten the differential to transmission bolts to 50 N·m(37 lb ft).

45. Connect the wiring harness retainer clip to the top of the differential.
46. Connect the wiring harness retainer to the stud at the differential rear cover.
47. Connect the vehicle speed sensor (VSS) electrical connector.
48. Raise the driveline into position.
49. Install the bolts attaching the driveline tunnel closeout panel to the underbody.
50. Install the exhaust pipe hanger bolts.
51. Install the right and left mufflers.
52. Install the rear wheel axle shafts to the differential.
53. Install the rear suspension crossmember.

•	Align the crossmember dowel pins to the holes in the frame rails.

•	Align the transaxle mount studs to the crossmember.

54. Install the rear suspension crossmember mounting nuts.

Tighten
Tighten the crossmember mounting nuts to 110 N·m(81 lb ft).

55. Remove the transmission jack from the crossmember.
56. Remove the adjustable jack stand from under the transmission.
57. Install the transaxle mount to rear crossmember nuts.

Tighten
Tighten the transaxle mount nuts to 50 N·m(37 lb ft).

58. Connect the wiring harness and brake pipe clip retainers to the rear suspension crossmember.
59. Install the spindle nuts retaining the rear wheel axle shafts to the hubs.

Tighten
Tighten the spindle nuts to 160 N·m(118 lb ft).

60. Install the bolts securing the upper control arms to the frame.

Tighten
Tighten the upper control arm bolts to 110 N·m(81 lb ft).

61. Install the shock absorber lower mounting bolts to the lower control arms.

Tighten
Tighten the shock absorber lower mounting bolts to 220 N·m(162 lb ft).

62. Connect the park brake cables to the park brake apply levers and brackets.
63. Connect the outer tie rod end studs to the rear suspension knuckles.
64. Install the outer tie rod end nuts.

Tighten

•	Tighten the outer tie rod end nuts to 20 N·m(15 lb ft) to seat the outer tie rod studs.

•	Turn the nuts additional 160 degrees.

•	Check the outer tie rod end nuts for a minimum torque of 45 N·m(33 lb ft).

65. Install the brake calipers to the caliper mounting brackets.

Tighten
Tighten the brake caliper guide pin bolts to 31 N·m(23 lb ft).

66. Connect the shock absorber solenoid electrical connectors, if equipped.
67. Connect the electronic suspension control (ESC) position sensor links, if equipped.
68. Connect the electrical connectors to both wheel speed sensors.
69. Remove J 33432-A Transverse Spring Compressor from the rear transverse spring.
70. Install the tire and wheel assemblies.
71. Refill the rear differential fluid. Refer to the Lubricant Change procedure in the Rear Axle sub-section of the Service Manual (SI Document ID #675189).
72. Refill the transmission fluid. Refer to the Transmission Fluid Replacement procedure in the Manual Transmission sub-section of the Service Manual (SI Document ID #765021).
73. Lower the vehicle.

Parts are currently available from GMSPO.

For vehicles repaired under warranty, use:

*This is a unique labor operation number for use only with this bulletin. This number will not be published in the Labor Time Guide.