Automatic Transmission - GMC T Series 1994 Repair Manual

AUTOMATIC TRANSMISSION UNIT REPAIR
NOTICE:
When fasteners are removed, always reinstall them at the same location from which they were removed.
If a fastener needs to be replaced, use the correct part number fastener for the application. If the correct part
number is not available, a fastener of equal size and strength (or stronger) may be used. Fasteners that are not
reused, and those requiring thread locking compound will be called out. The correct torque value must be used
when installing fasteners that require it. If the above conditions are not followed, parts or system damage could
result.
Transmission D isassem bly......................... .4L80-E- 2
Converter Assembly/Speed Sensors...... .4L80-E- 2
Pan and Filter Assembly.......................... .4L80-E- 2
Control Valve Assembly.......................... .4L80-E- 3
Front and Rear Servo............................... .4L80-E- 4
Band Apply Pin C heck............................ . 4L80-E- 5
Case Extension A ssem bly....................... .4L80-E- 6
Parking Lock Pawl and Actuator
Assem bly.............................................. .4L80-E- 6
Front End Play Check.............................. .4L80-E- 8
Rear Unit End Play C h eck ...................... .4L80-E- 8
Pump Assembly........................................ .4L80-E- 9
Overdrive Unit and
Fourth Clutch Assembly..................... .4L80-E-10
Forward Clutch A ssem bly....................... .4L80-E-11
Direct Clutch Assembly........................... .4L80-E-11
Intermediate Clutch Assembly................ .4L80-E-11
Center Support and Gear Unit Assembly
and Rear B and...................................... .4L80-E-12
Inspect, Clean and Repair Subassemblies ..4L80-E-13
Parking Lock Pawl and Actuator
Assem bly.............................................. .4L80-E-14
Transmission C ase.................................... .4L80-E-14
Rear Band and Selective
Thrust Washer....................................... .4L80-E-15
Gear Unit and Output Assemblies.......... .4L80-E-15
Reaction Drum and Carrier Assembly.... .4L80-E-18
Center Support Assem bly........................ .4L80-E-18
Gear Unit A ssem bly................................ .4L80-E-20
Direct Clutch Assembly........................... .4L80-E-22
Intermediate Clutch Assembly and
Front B and............................................ .4L80-E-25
Forward Clutch Assembly....................... .4L80-E-25
Fourth Clutch Assembly.......................... .4L80-E-29
4th Clutch Travel C heck.......................... .4L80-E-30
Overdrive Unit Assem bly........................ .4L80-E-30
Overrun Clutch A ssem bly....................... .4L80-E-31
Overdrive Carrier Assembly................... .4L80-E-33
Turbine S h aft............................................ .4L80-E-34
Pump Assembly.................... ................... .4L80-E-35
Front Servo A ssem bly............................. .4L80-E-39
SECTION 7A-17B
HYDRA-MATIC 4L80-E
RPO MT1
CONTENTS
Rear Servo Accumulator...........................4L80-E-39
Control Valve Assembly/Accumulator
Accumulator Housing Assembly..............4L80-E-41
Control Valve Assem blv......................... ..4L80-E-41
Case Extension A ssem bly..................... ...4L80-E-44
Speed Sensor Assem blies...................... ...4L80-E-44
Torque Converter A ssem bly.................. ...4L80-E-45
Transmission Reassembly.............................4L80-E-46
Parking Lock Pawl and Actuator
Rear Band and Selective
Center Support and Gear
Rear Unit End Play C h eck .................... ...4L80-E-47
Intermediate Clutch Assembly/Direct
Clutch Assembly..................................... ...4L80-E-49
Forward Clutch A ssem bly..................... ...4L80-E-49
4th Clutch A ssem bly............................. ...4L80-E-49
Turbine Shaft and Overdrive
Fourth Clutch P lates.............................. ...4L80-E-51
Pump Assembly...................................... ...4L80-E-52
Front Unit End Play C h eck ................... ...4L80-E-52
Front Servo A ssem bly........................... ...4L80-E-53
Band Apply Pin C h eck ........................... ...4L80-E-54
Rear Servo Accum ulator....................... ...4L80-E-55
Control Valve A ssem bly........................... ...4L80-E-56
Installing Control Valve Assembly
Pan and Filter Assembly........................ ...4L80-E-57
Case Extension A ssem bly..................... ...4L80-E-57
Speed Sensor Assemblies...................... ...4L80-E-59
Torque Converter Assembly................. ...4L80-E-59
Disassembled V iew s.............................. ...4L80-E-68
Bushing and Bearing Locations........... ...4L80-E-69
Lip Seal Locations................................ ...4L80-E-70
Specifications............................................. ...4L80-E-71
Fastener Tightening Specifications..... ...4L80-E-71
Special Tools.............................................. ...4L80-E-72
H ousing............................................... ...4L80-E-41
Assembly............................................. ...4L80-E-46
Thrust Washer...................................... ...4L80-E-46
Unit Assembly.................................... ...4L80-E-47
Carrier Assembly............................... ...4L80-E-51
and Accumulator Assembly.............. ...4L80-E-56