8HP45 Automatic Transmission - Disassembly

DISASSEMBLY

Special Tools:

CAUTION: The Transmission Control Module (TCM), or Transmission Control Module Assembly (TCMA) is extremely sensitive to Electrostatic Discharge (ESD). Always use a ground strap and follow the ESD guidelines in ELECTROSTATIC DISCHARGE (ESD) SENSITIVE DEVICES . Failure to follow these instructions may result in damage to the TCM/TCMA.

NOTE: If the transmission is being reconditioned (clutch/seal replacement) or replaced, it is necessary to perform the TCM Adaptation Procedure 8HP45

NOTE: Tag all clutch pack assemblies, as they are removed, for reassembly identification.

NOTE: RWD Shown, AWD similar.

1. Remove the torque converter (1).

NOTE: AWD only.

2. Remove the seven transmission housing extension bolts (2) and remove the housing (1).
3. Remove the transmission rear oil seal (3) with a suitable slide hammer and screw.

NOTE: AWD only.

4. Remove the input shaft snap ring (1) and washer.

NOTE: RWD only.

5. Using a suitable punch, remove the staking from the propeller shaft flange nut, and loosen the nut about 1 thread using a 34 mm 12 point socket (3) and (C-3281)(2) to hold the flange (1).

NOTE: RWD shown, AWD similar.

NOTE: End play specification is between 0.11 - 0.42 mm (0.0043 - 0.0165 in.). If end play is outside this range, a different selectable end play shim must be used during assembly.

6. Measure the output shaft (1) end play as follows:
a. Attach a dial indicator (2) and position the plunger against the end of the output shaft (1).
b. Zero the dial indicator (2).
c. Move the output shaft (1) in and out , and record the maximum travel for assembly reference.

NOTE: RWD only.

7. Finish removing the propeller shaft flange nut.
8. Remove the propeller shaft flange (1).
9. Remove the transmission rear dust seal (2).
10. Remove the transmission rear oil seal (3) with a suitable slide hammer and screw.
11. Remove the transmission output shaft washer.

12. Remove the thirteen oil pan retaining bolts (2).

NOTE: Inspect the gasket for reuse. If the seal is cut or torn, replace the gasket.

13. Carefully detach the oil pan (1) and gasket.

14. Remove the valve body assembly end retainer bolts (3).
15. Lift the electrical connector lock (2) to release the internal harness end from inside the transmission for valve body assembly removal.
16. Remove the sensor retaining bolt (1) and pull the sensor (4) loose from the case.

17. Using (10377) (1) carefully pull the electrical harness insulator (2) straight out from the transmission case (3).

18. Remove valve body assembly retaining bolts 1-14 (15-18 are already removed).
19. Carefully lift the valve body assembly from the transmission.

NOTE: The fluid port (1) may be in the transmission or the valve body assembly.

20. Pull the fluid port (1) from the transmission or valve body assembly.
21. Remove the two O-rings (2).
22. Remove the compression seal (3) from the transmission.

23. Remove the thirteen oil pump housing retaining bolts (2).

24. Remove the input shaft O-ring (1) using a small pick (2) or equivalent.

25. Carefully pry the oil pump housing (1) away from the case (2) with a small flat blade screwdriver (3) or equivalent through the case opening.
26. From the front of the transmission, remove the oil pump housing.

NOTE: Apply air pressure slowly because oil may spray when B-piston releases from the assembly.

27. With one hand above B-piston (1), carefully apply air pressure into the hole (2) directly above the B-piston alignment tab (3) to remove B-piston (1) from the assembly.

28. Remove the outer ring (1) (under B-piston).
29. Remove the snap ring (2).
30. Remove the clutches and spacers (4).
31. Remove the hub (3).

32. Position the oil pump housing assembly (4) in a suitable arbor press.
33. Using (8285) (1), press on the fingers of the piston retaining ring to remove tension, and remove the two halves of the split retainer ring (2, 3).

34. Remove the piston retaining ring and piston below it.

35. Remove the five bolts (1) and separate the oil pump housing (2) from the oil pump cover (3).

36. Using (9667) (2) and (C-3752) (1), remove the oil seal from the front pump cover.
37. Remove the outer lip seal from the front pump cover.

38. Remove the manual park release lever retaining nut (2) and remove the lever (1).

39. Remove the three park pawl lock rod guide plate retaining screws (1) and remove the plate (2).

40. Remove the park pawl lock rod (1) from the fork (2).

NOTE: Pay attention to the spring position for installation.

41. Remove the roll pin from the selector shaft (4) using a suitable pin punch (3).
42. Remove the shaft (4), spring (2) and fork (1) from the case.
43. Remove the selector shaft seal using a small screwdriver or equivalent.

44. Remove the park pawl shaft plug (1) from the rear of the case.

NOTE: Pay attention to the spring position for installation.

45. Remove the park pawl shaft using a suitable pin punch (3), remove the park pawl (1) and spring (2).

46. Remove the input/output shaft and P4 annulus drum assembly (1) from the case.

NOTE: AWD shown, RWD similar. The AWD bearing is a needle bearing and the RWD is a ball bearing.

47. Remove the outer bearing snap ring (1), and the outer needle bearing (2) (AWD) or outer ball bearing (RWD).

NOTE: AWD shown, RWD similar.

48. Remove the oil dam snap ring.
49. Using (9664) (1) and (C-637) (2), remove the oil dam (3).

NOTE: AWD shown, RWD similar.

50. Remove the output shaft inner needle bearing snap ring.
51. Using (9664) (1) and (C-637) (2) , remove the inner needle bearing (3).

52. Position the input/output shaft and P4 annulus drum assembly (1) on (8925-3) (3) and (1130) (4).
53. Remove the clutch pack (2).

54. Remove the O-ring and 5 squared O-rings.
55. Remove the P1 annulus/B clutch hub assembly (1) from the P4 annulus drum.

NOTE: The washer may stick to the bottom of the P1 annulus/B clutch hub assembly (1).

56. Remove the washer from the internal ring gear.
57. Remove the needle bearing and holding plate (2) from the P1 planetary carrier.

NOTE: The (10378) are three pieces intended to be used in multiple locations around the drum.

58. Position the (10378) (1) on the P4 annulus drum assembly to protect the drum.

NOTE: Pry the snap ring from the opposite side of the snap ring openings to release.

NOTE: When the snap ring is removed the internal clutch drum may drop slightly.

59. Using a suitable tool (3), release the snap ring (2) by prying in and up from the opposite side of the snap ring openings.

60. Remove the P1 planetary carrier (3).
61. Remove P1/P2 sun gear from the bottom of the P1 planetary carrier (3).

62. Remove the input shaft with P2 planetary carrier (1) from the drum assembly.
63. Remove the needle bearing (2) and washer.

64. Remove the P2 annulus/P3 sun gear (1) from the drum assembly (2).

65. Remove the D clutch drum (1) from the P4 annulus drum (2).

NOTE: The (10378) are three pieces intended to be used in multiple locations around the drum.

66. Position the (10378) (4) on the P4 annulus drum assembly to protect the drum.
67. Using a suitable tool (1), release and remove the snap ring (2).
68. Remove the P3 planetary carrier (3).
69. Remove the needle bearing from the planetary carrier.

70. Remove the P4 sun gear/C/E clutch retainer (1) from the D clutch drum (2).

71. Remove the snap ring (1) from the P4 sun gear/C/E clutch retainer (2).

72. Remove the P3 annulus (1) from the P4 sun gear/C/E clutch retainer (2).

73. Remove the snap ring (1) from the P4 sun gear/C/E clutch retainer (2).

74. Remove the E clutch (1) from the P4 sun gear/C/E clutch retainer (3).
75. Remove the needle bearing (2) from the E clutch (1).

76. Remove the C clutch (1) from the P4 sun gear/C/E clutch retainer (2).
77. Remove the bearing from top and bottom of C clutch (1).

78. Remove the P4 planetary carrier/output shaft (2) from the P4 annulus drum (1).

79. Remove the snap ring (1) from the P4 annulus drum (2).
80. Remove the P4 annulus (3) from the P4 annulus drum (2).