Automatic Transmissions and

Fundamentals of Operation

THIRD EDITION

MATHIAS F. BREJCHA Professor Emeritus Automotive and Heavy Equipment Department Ferris State University Big Rapids, Michigan

REGENTS/PRENTICE HALL Englewood Cliffs, New Jersey 07632 Contents

Preface IX Acknowledgments xi Chapter 1 Introduction to Automatic Transmissions/Transaxles and the Powertrain

Introduction, 1 Final Drive and Differential, 6 All-Wheel Drive/Four-Wheel Drive, 11 The Powertrain, 2 Converter, 3 Review Questions, 15 and Engine, 3 Chapter 2 Hydrodynamics Units 17

Terminology: Hydrodynamic Drives, 18 Cooling the Hydraulic Fluid, 29 Operating Characteristics, 34 Fluid Coupling, 19 Converter/Engine Match, 34 Function and Construction, 19 Operation, 20 Lockup Converter, 34 Speed Ratio, 20 Hydraulically Applied Piston, 36 Centrifugal Locking Clutch, 41 Fluid , 23 Planetary Splitter Gear Converter, 45 Function and Construction, 23 Direct Mechanical Converter, 45 Operation, 24 Torque and Coupling Phases, 27 Review Questions, 48 Chapter 3 Planetary Gears in Transmissions 50

Gears and Gear Ratios, 50 Planetary Gear Assembly, 54 Gearing Definitions, 53 Laws of Planetary Gear Operation, 54

Contents v Law of Neutral, 54 Planetary Variations, 64 Law of Reduction, 55 Planetary Systems, 66 Law of , 61 Law of Direct Drive, 62 Simpson Gear System, 67 Law of Reverse, 64 Ravigneaux Gear System, 69 Combining Gear Reduction and Direct Drive, 64 Review Questions, 72 Planetary Driving , 64 Chapter 4 Planetary Gear Systems in Automatic Transmissions/Transaxles 75

Simpson Planetary System: Three-Speed , Powertrain Assembly, 88 Torqueflite, 75 Operating Characteristics, 91 Planetary Powerflow, 91 Powertrain Assembly, 75 Operating Characteristics, 75 Ravigneaux Planetary System: Three-Speed Ford Planetary Powerflow, 77 ATX, 93 Simpson Low-Gear Formula, 82 Ravigneaux Planetary System: Four-Speed Ford Simpson Planetary System: Three-Speed Ford, 82 AOD, 93 Powertrain Assembly, 82 Ravigneaux Gear Ratio Calculation, 93 Operating Characteristics, 85 Planetary Overdrive Systems, 94 Planetary Powerflow, 85 THM 200-4R, 4L30, 4L80, 94 Simpson Planetary System: Three-Speed General Ford A4LD, 99 Motors Products, 88 Chrysler A-500, 100 Operating Characteristics, 88 Review Questions, 104 Ravigneaux Planetary System: Three-Speed GM THM-180/180C(3L30), 88 Chapter 5 Hydraulic Fundamentals 112

Fluid and the Hydraulic Lever, 112 An Actuating Mechanism, 118 Pascal's Law, 113 Finally the Lines, 118 Force/Pressure Relationship, 114 The Complete System, 118 Conservation of Energy and the Hydraulic Lever, 115 Flow in a Circuit, 118 Summary of the Fundamental Laws of Hydraulics, 116 Hydraulic Jack, 118 Intake Stroke, 119 Basic Hydraulic System, 116 Power Stroke, 119 First a Reservoir, 116 Lowering, 119 Then a Pump, 116 ThenValving, 118 Review Questions, 119 Chapter 6 Hydraulic System Fundamentals: Pumps and Valves 122

Hydraulic Pumps, 122 Check Valves, 129 Basic Operation, 122 Relief Valves, 129 Pump Drives, 123 Spool Valves, 130 IX Rotary Pumps, 123 Regulator Valves, 133 Variable-Capacity Vane Pump, 126 Relay Valves, 134 Hydraulic Orifice, 127 Review Questions, 135 Hydraulic Valves, 129

vi Contents Chapter 7 Hydraulic Control System: Fundamentals of Operation 137

Pump and Pressure Regulation System, 137 Clutch Plate Design, 157 Converter-Cooling-Lubrication System, 138 Valve Body Assembly, 159 Throttle/Modulator Systems, 142 Accumulator, 161 Throttle Valve Control, 142 Shift System, 164 Modulator System, 146 Neutral/Park, 164 Modulator System Variation, 147 Automatic Drive Range, 164 Manual Control System, 148 Coast or Closed-Throttle Downshift, 166 Part-Throttle 3-2 Downshift Governor System, 150 Full-Throttle Forced Downshift, 170 Servo and Clutch Assemblies, 151 Intermediate and Manual Low, 173 Servo Assembly, 151 Reverse, 175 Band Design, 154 Review Questions, 176 Clutch Assembly, 154 Chapter 8 Electronification: Electronic Theory, Shift Systems, and Converter Clutch Circuit Controls 181

Electricity Is Electronics, 181 Current Flow, 194 Series Circuits, 195 Current Flow (Electron Theory), 182 Parallel Circuits, 197 Matter and the Atom, 182 Series-Parallel Circuits Electron Flow Theory, 183 Conductors and Nonconductors, 183 Wiring Diagrams, 198 Creating Electricity, 185 Computer Electronics, 198 Magnetism and Electricity, 186 Computer Inputs, 200 Permanent Magnets, 186 Computer Outputs, 200 Electromagnetism, 187 Switch Sensors, 200 Electromagnetic Fields, 187 Converter Clutch Control Circuits, 202 Electromagnetic Induction, 189 Chrysler Corporation, 202 Self-induction, 189 Mutual Induction, 191 , 210 Electrical Units, 191 General Motors Corporation, 212 Voltage, 191 Electronic Shift Control, 226 Current, 192 Electronic Shift Basics, 227 Resistance, 193 Shift Solenoid Operation, 227 Ohm's Law, 193 Combined Hydraulic/Electronic Shift Systems, 239 Electrical Circuits, 194 Pulse Generator, 239 Basic Circuit Components, 194 Review Questions, 242

Contents vii Chapter 9 Summary Review of Current Automatic Transmissions/Transaxles 250

Chrysler Corporation, 250 AXOD (FWD/Automatic Overdrive ), TorqueFlite A-904/900 Series and A-727, 250 311 TorqueFlite A-400 Series and A-670, 254 AXOD-E (Electronic Controlled), 321 A-500 Four-Speed Overdrive Series, 258 4EAT (FWD Automatic Overdrive), 327 A-604 , 262 General Motors Corporation, 338 Ford Motor Company, 278 THM 400/475 (3L80/3L80-HD), 338 AOD (RWD/Automatic Overdrive Hydra-Matic 4L80-E, 341 Transmission), 278 THM 125/125C (3T40) and A-l (3T40-A), 345 AOD-E (Electronic Controlled), 288 4L60 (THM 700-R4), 350 A4LD (RWD/Light-Duty Overdrive 4T60 (THM 440-T4), 361 Transmission), 290 4T60-E, 370 E40D (RWD/Truck Automatic Overdrive 4L30-E(THM-R1), 374 Transmission), 293 Review Questions, 379 ATX (FWD Transaxle), 298 Appendix 394

A: Metric-English Conversion Table, 395 C: Decimals-Metric Equivalents, 397 B: Direct-Reading Metric-English Conversion, 396 D: Newton-Meters/Pound-Feet Equivalents, 398 Glossary 399 Index I Electrical/Electronics Basics 412 Index II Transmsission/Transaxle Fundamentals of Operation 415

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