Overhaul Procedure Steps

4L60-E/4L65-E/4L70-E - Automatic TransmissionNOTE: This article lists the sequential steps necessary to overhaul the transmission.
^ For the specific step listed below, refer to that step under "Repair Instructions". Repair Instructions

6L45;6L50;6L80;6L90

1. Torque Converter Removal and Holding Fixture Installation
2. Case Extension Assembly Removal
3. Transmission Fluid Pan, Filter and Electrical Connector Passage Sleeve Removal
4. Control Valve Body Assembly Removal
5. Torque Converter Housing with Fluid Pump Removal
6. 1-2-3-4 and 3-5 Reverse Clutch Assembly and 4-5-6 Clutch Assembly Removal (6L50/80/90)
7. Center Support, Output Carrier and Output Shaft Removal (6L80/6L90)
8. Manual Shift Shaft and Parking System Components Overhaul (6L80/6L90)
9. Manual Shift Shaft Seal Replacement
10. Output Shaft Seal Replacement (AWD Models Only)
11. Case Inspection
12. Output Shaft Disassemble (6L80/6L90)
13. Output Internal Gear Disassemble (6L80/6L90)
14. Output Shaft Assemble (6L80/6L90)
15. Output Carrier Assembly Overhaul (Gas)
16. Output Carrier Assembly Overhaul (Diesel)
17. Output Carrier to Output Shaft Assemble (6L80/6L90)
18. Output Carrier to Output Internal Gear Assemble (6L80/6L90)
19. 2-6 Clutch Overhaul (Gas)
20. 2-6 Clutch Overhaul (Diesel)
21. Low and Reverse Clutch Overhaul (Gas)
22. Low and Reverse Clutch Overhaul (Diesel)
23. Low and Reverse Clutch Backing Plate Retaining Ring Measurement
24. 4-5-6 Clutch Dampener Overhaul (6L50/80/90)
25. 4-5-6 Clutch Overhaul (Gas)
26. 4-5-6 Clutch Overhaul (Diesel)
27. 4-5-6 Clutch Backing Plate Retaining Ring Measurement
28. 1-2-3-4 and 3-5 Reverse Clutch Overhaul (Gas)
29. 1-2-3-4 and 3-5 Reverse Clutch Overhaul (Diesel)
30. 1-2-3-4 Clutch Backing Plate Retaining Ring Measurement
31. 3-5 Reverse Clutch Backing Plate Retaining Ring Measurement (6L80/6L90)
32. Torque Converter Housing with Fluid Pump Disassemble
33. Fluid Pump Cover Cleaning and Inspection
34. 1-2-3-4 and 3-5 Reverse Clutch Fluid Seal Ring Installation (6L80/6L90)
35. Torque Converter Housing Cleaning and Inspection
36. Torque Converter Fluid Seal Replacement
37. Transmission Fluid Cooler Pipe Seal Replacement
38. Fluid Pump Selective Measurement
39. Torque Converter Housing with Fluid Pump Assemble
40. Fluid Pump Cover Installation
41. Control Valve Body Assembly Disassemble
42. Control Valve Lower Body Assembly Cleaning and Inspection
43. Control Valve Upper Body Assembly Cleaning and Inspection
44. Control Valve Body Assembly Assemble
45. Center Support, Output Carrier and Output Shaft Installation (6L80/6L90)
46. 1-2-3-4 and 3-5 Reverse Clutch Assembly and 4-5-6 Clutch Assembly Installation (6L80/6L90)
47. Torque Converter Housing with Fluid Pump Installation
48. Propeller Shaft Front Slip Yoke Oil Seal Replacement
49. Control Valve Body Assembly Installation
50. Automatic Transmission Electrical Connector Passage Sleeve Installation
51. Fluid Filter and Manual Shift Detent Assembly Installation
52. Transmission Fluid Pan Installation
53. Case Extension Assembly Installation
54. Torque Converter Installation and Holding Fixture Removal