null

GM 8L90 TechTran

$45.00
SKU:
8L90
Shipping:
Free US shipping
Adding to cart… The item has been added

Product Overview

HYDRA-MATIC 8L90 Manual - The 8L90 transmission is a fully automatic eight speed rear wheel drive transmission that is available in both two and four wheel drive configurations. It features clutch to clutch shifting which provides eight forward and one reverse gear. It also uses a four element lockup torque converter, four planetary gear sets as well as five multiple disc and one mechanical clutch set. The 8L90 utilizes an off axis chain drive pump to maintain fluid volume and operating pressures. The externally located TCM controls the changing of gear ratios through the use of solenoids and also controls transmission line pressure through the use of a variable force motor. The TCM will also control converter clutch operation. The 8L90 has undergone some parts changes from it’s inception until the present. Some of those changes are indicated in this manual and some are not. The transmission in this manual was disassembled and reassembled without all factory tools, if all factory tools are used, the transmission would be assembled differently than shown in this manual. For clarity this manual will address the disassembly and assembly procedures for the 8L90 and is intended for use by the professional technician.

GENERAL DESCRIPTION AND VEHICLE APPLICATION CHART........................ 3

COMPONENT IDENTIFICATION AND APPLICATION CHART............................... 4

SHIFT QUADRANT OPERATION.................................................................................... 5

IDENTIFICATION TAG INFORMATION AND SPECIFICATIONS.......................... 7

TRANSMISSION FLUID REQUIREMENT, DRAIN, FILL AND CHECK PROCEDURES........... 8

TRANSMISSION LINE PRESSURE SPECIFICATIONS.............................................. 9

ELECTRONIC COMPONENT OPERATION................................................................. 10

SOLENOID IDENTIFICATION AND APPLICATION CHART.................................. 11

MANUAL SHIFT SHAFT POSITION SWITCH OPERATION................................... 12

TRANSMISSION SPEED SENSOR OPERATION........................................................ 13

TRANSMISSION FLUID TEMPERATURE SENSOR & INTERNAL MAIN HARNESS ID  .............. 14

TRANSMISSION CASE CONNECTOR TERMINAL ID.............................................. 15

WIRING DIAGRAM EXAMPLE...................................................................................... 16

HIGH PRESSURE ACCUMULATOR STOP/START OPERATION............................ 18

DIAGNOSTIC TROUBLE CODES.................................................................................. 19

SOLENOID CHARACTERIZATION PROGRAMMING.............................................. 22

TRANSMISSION DISASSEMBLE.................................................................................. 23

COMPONENT REBUILD SECTION

1-3-5-6-7 CLUTCH HOUSING - DISASSEMBLE......................................................... 40

1-3-5-6-7 CLUTCH HOUSING - ASSEMBLE................................................................ 43

2-3-4-6-8/4-5-6-7-8-R CLUTCH HOUSING - DISASSEMBLE................................... 48

2-3-4-6-8/4-5-6-7-8-R CLUTCH HOUSING - ASSEMBLE........................................... 54

EXTENSION HOUSING - DISASSEMBLE................................................................... 68

EXTENSION HOUSING - ASSEMBLE.......................................................................... 71

FRONT COVER - DISASSEMBLE.................................................................................. 74

FRONT COVER - ASSEMBLE......................................................................................... 75

CONTROL VALVE BODY - DISASSEMBLE, INSPECT & REASSEMBLE............. 76

TRANSMISSION ASSEMBLE....................................................................................... 101

TRANSMISSION FINAL ASSEMBLE.......................................................................... 122

AIR CHECK LOCATIONS.............................................................................................. 134

TORQUE SPECIFICATIONS......................................................................................... 135

SPECIAL TOOLS.............................................................................................................. 136