INDEX

Copyright ATSG 1999

G.M. 4T80-E

2

POWERFLOW AND SOLENOID CHARTS............................. ............................................................................... 4SOLENOID LOCATIONS.................................................................. ........................................................................ 5ELECTRONIC CONTROLS DESCRIPTION......................................................................................................... 6TROUBLE CODE CHART ......................................................................................................................................... 11ONBOARD DIAGNOSTIC............................................................. ........................................................................... 12WIRE SCHEMATIC.................................................................... .............................................................................. 14CASE CONNECTOR PIN I.D............................................................. ....................................................................... 16LINE PRESSURE TEST....................................................................... ...................................................................... 18OIL PASSAGE I.D............................................................. .......................................................................................... 29CASE COVER CHECKBALL LOCATIONS............................................................................................................ 33LOWER VALVE BODY CHECKBALL LOCATIONS............................................................................................. 35ACCUMULATOR HOUSING CHECKBALL LOCATIONS.................................................................................. 36TRANSAXLE DISASSEMBLY................................................................................................................................... 38COMPONENT SUB-ASSEMBLY............................................................................................................................... 53TRANSAXLE RE-ASSEMBLY................................................................................................................................... 77INPUT SHAFT END-PLAY MEASUREMENT......................................................................................................... 85FINAL DRIVE END-PLAY MEASUREMENT.......................................................................................................... 92TORQUE SPECIFICATIONS................................................................................................................................... 102BOLT LOCATIONS AND IDENTIFICATION........................................................................................................ 104AIR CHECKING PROCEDURES............................................................................................................................ 108SPECIAL TOOL REQUIREMENTS........................................................................................................................ 112

AUTOMATIC TRANSMISSION SERVICE GROUP18639 S.W. 107TH AVENUEMIAMI, FLORIDA 33157

(305) 670-4161

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INTRODUCTION

THM 4T80-E

1

No part of any ATSG publication may be reproduced, stored in any retrieval system or transmitted in any form or by any means, including but not limited to electronic, mechanical, photocopying, recording or otherwise, without written permission of Automatic Transmission Service Group. This includes all text illustrations, tables and charts.

"Portions of materials contained herein have been reprinted underlicense from General Motors Corp, Service & Parts Operations."

The information and part numbers contained in this booklet havebeen carefully compiled from industry sources known for their

reliability, but ATSG does not guarantee its accuracy.

Copyright ATSG 2003

UpdatedOctober, 2003

DALE ENGLANDFIELD SERVICE CONSULTANT

ED KRUSETECHNICAL CONSULTANT

WAYNE COLONNATECHNICAL SUPERVISOR

PETER LUBANTECHNICAL CONSULTANT

JIM DIALTECHNICAL CONSULTANT

GREGORY LIPNICKTECHNICAL CONSULTANT

JERRY GOTTTECHNICAL CONSULTANT

JON GLATSTEINTECHNICAL CONSULTANT

DAVID CHALKERTECHNICAL CONSULTANT

ROLAND ALVAREZTECHNICAL CONSULTANT

MIKE SOUZATECHNICAL CONSULTANT

GERALD CAMPBELLTECHNICAL CONSULTANT

This booklet contains the general description, diagnosis charts, and the procedures necessary to overhaul, repair or service the General Motors THM 4T80-E four speed automatic overdrive transaxle. This information will assist you in training your technicians to provide your customers with the best possible transmission service that is available.The THM 4T80-E is a fully automatic, front wheel drive, electronically controlled transaxle. It provides four forward speeds with 4th gear being overdrive. Shift points are controlled by the Powertrain Control Module (PCM) with two shift solenoids. Oil pressure is supplied by two gear type pumps. Oil pressure is regulated by the PCM using a Pressure Control Solenoid. Shift schedule and TCC apply rates are also controlled by the PCM and are influenced by many inputs from various sensors on the vehicle.

AUTOMATIC TRANSMISSION SERVICE GROUP18639 S.W. 107TH AVENUEMIAMI, FLORIDA 33157

(305) 670-4161