- Overhaul Procedure Steps
4T80-ENOTE: This article lists the sequential steps necessary to overhaul the transmission.
For the specific step listed below, refer to the hyperlink for that step.
For the complete list of procedures, refer to "Repair Instruction".
Overhaul
OVERHAUL PROCEDURE:
Torque Converter and Oil Pump Drive Shaft Removal
Torque Converter and Oil Pump Drive Shaft Removal
Holding Fixture Installation
Holding Fixture Install
Vehicle Speed Sensor (OSS) and Cooler Fitting Removal
OSS Sensor and Cooler Fitting Removal
Fourth Servo Removal
Fourth Servo Removal
Final Drive End Play Measurement
Final Drive End Play Measurement
Case Extension and Scavenge Pipe Removal
Case Extension and Scavenge Pipe Removal
Differential Carrier and Housing Removal
Differential Carrier and Housing Removal
Output Shaft Removal
Output Shaft Removal
Final Drive Carrier, Sun and Internal Gear Removal
Final Drive Carrier, Sun and Internal Gear Removal
Bottom Pan, Gasket, and Scavenge Screens Removal
Bottom Pan, Gasket, and Scavenge Screens Removal
Lower Control Valve Body Assembly Removal
Lower Control Valve Body Assembly Removal
Input Shaft End Play Measurement
Input Shaft End Play Measurement
Side Cover, Gasket, and Filter Removal
Side Cover, Gasket, and Filter Removal
Oil Pump, Upper Control Valve Assembly Removal
Oil Pump, Upper Control Valve Assembly Removal
Case Cover Removal
Case Cover Removal
Drive/Driven Sprocket and Chain Removal
Drive/Driven Sprocket and Chain Removal
Input Speed Sensor and Wiring Harness Removal
Input Speed Sensor and Wiring Harness Removal
2ND Clutch Plates and Reverse Clutch Removal
2ND Clutch Plates and Reverse Clutch Removal
4TH Band and 3RD Clutch/Reaction Shell Removal
4TH Band and 3RD Clutch/Reaction Shell Removal
Parking Pawl Removal
Parking Pawl Removal
Forward Clutch ASM and Low Reverse Band Removal
Forward Clutch ASM and Low Reverse Band Removal
Manual Shaft Assembly Removal
Manual Shaft Assembly Removal
Case Inspection
Case Inspection
Drive Sprocket Support and Seal Replacement
Drive Sprocket Support and Seal Replacement
Forward and Coast Clutch Assembly Overhaul
Forward and Coast Clutch Assembly Overhaul
Fretting Ring Installation
Fretting Ring Inspection and Installation
Forward and Coast Clutch Installation
Forward and Coast Clutch Installation
Final Drive Gear and Snap Ring Installation
Final Drive Gear and Snap Ring Installation
Forward Clutch Support Stud Installation
Forward Clutch Support Stud Installation
Parking Pawl and Pivot Pin Install
Parking Pawl and Pivot Pin Install
Third Clutch and Reaction Carrier Disassemble
Third Clutch and Reaction Carrier Disassemble
Third Clutch and Reaction Carrier Assemble
Third Clutch and Reaction Carrier Inspect/Assemble
Reaction Carrier/Shell and 3RD Clutch Installation
Reaction Carrier/Shell and 3RD Clutch Installation
4TH Band Installation
4TH Band Installation
Reverse Clutch Housing and 2ND Sprag Disassemble
Reverse Clutch Housing and 2ND Sprag Disassemble
Reverse Clutch Housing and 2ND Sprag Assemble
Rev Clutch Housing and 2ND Sprag Inspect/Assemble
Reverse Clutch Housing Installation
Reverse Clutch Housing Installation
2ND Clutch Plated Installation
2ND Clutch Plates Inspection and Installation
Driven Sprocket Support Disassemble
Driven Sprocket Support Disassemble
Driven Sprocket Support Assemble
Driven Sprocket Support Inspect and Assemble
Drive Link and Sprockets Assemble
Drive Link and Sprockets Inspect/Assemble/Install
Thrust Bearings Installation
Thrust Bearings Inspect and Install
Case Cover/Turbine Shaft Seal Replacement
Case Cover Inspect and Install/Seal Replace
Case Cover Assembly Installation
Case Cover Assembly Installation
Input Shaft End Play Measurement 2
Input Shaft End Play Measurement
Upper Control Valve Body Disassemble
Upper Control Valve Body Disassemble and Inspect
Upper Control Valve Body Assemble
Upper Control Valve Body Assemble
Upper Control Valve Assembly Installation
Upper Control Valve Assembly Installation
Pump Disassemble
Pump Disassemble
Secondary Pump Disassemble
Secondary Pump Disassemble and Inspect
Secondary Pump Assemble
Secondary Pump Assemble
Pump Assemble
Pump Inspect and Assemble
Pump Installation
Pump Installation
Temp Sensor, TCC Solenoid and PCS Valve Assemble
Temp Sensor, TCC Solenoid, and PCS Valve Assemble
Oil Filter and Side Cover Install
Oil Filter and Side Cover Install
Lower Control Valve Body Assembly Disassemble
Lower Control Valve Body Disassemble and Inspect
Channel Plate Assemble
Channel Plate Inspect and Assemble
Lower Control Valve Body Disassemble
Lower Control Valve Body Disassemble and Inspect
Lower Control Valve Body Assemble
Lower Control Valve Body Inspect and Assemble
Lower Control Valve Body and TFP Switch Install
Lower Control Valve Body and TFP Switch Install
Accumulator Housing Disassemble
Accumulator Housing Disassemble and Inspect
Accumulator Housing Assemble
Accumulator Housing Assemble and Installation
Lower Controls Assembly Installation
Lower Controls Assembly Installation
Manual Link and Electrical Connectors Installation
Manual Link and Electrical Connectors Installation
Scavenge Screens/Seals, Bottom Pan Installation
Scavenge Screens/Seals, Bottom Pan Inspect/Install
Final Drive Carrier Inspect
Final Drive Carrier Inspect
Differential Carrier Overhaul
Differential Carrier Overhaul
Final Drive Carrier/Differential Carrier Install
Final Drive Carrier/Differential Carrier Install
Output Shaft Installation
Output Shaft Inspect and Install
Case Extension/Scavenge Pipe Installation
Case Extension/Scavenge Pipe Inspect and Install
Final Drive End Play Measurement 2
Final Drive End Play Measurement
4TH Servo Overhaul
4TH Servo Overhaul
OSS Sensor and Cooler Fitting Installation
VSS Sensor and Cooler Fitting Inspect and Install
Axle Seals Replacement
Axle Seals Removal and Installation
Torque Converter and Oil Pump Drive Shaft Install
Torque Converter and Oil Pump Drive Shaft Install