John Deere 8120 8220 8320 8420 and 8520 Tractors Repair Technical Manual TM1970 04MAR21

Table of contents
FOREWORD
DEALER PREDELIVERY INFORMATION FORM
Section 10 – GENERAL INFORMATION
Group 05 – Safety
Group 10 – General Information
Section 20 – ENGINE
Group 00 – Component Removal and Installation
Group 05 – Engine Repair
Section 30 – FUEL AND COOLING SYSTEMS
Group 05 – Diesel Fuel System
Group 10 – Air Intake System
Group 15 – Engine Cooling System
Group 20 – Coolers and Air Conditioning Condenser
Section 40 – ELECTRICAL
Group 05 – Connectors
Group 10 – Wiring Harness Routings
Group 15 – Charging Circuit
Group 20 – Starting Circuit
Group 25 – Relays, Fuses, Solenoids, and Switches
Group 30 – Monitoring Systems and Sensors
Group 35 – Armrest Control
Group 40 – Implement and Accessory Connectors
Group 45 – Convenience and Accessory Components
Section 50 – POWER SHIFT TRANSMISSION
Group 00 – Component Removal and Installation
Group 05 – Miscellaneous Repair
Group 10 – Transmission
Section 56 – DRIVE SYSTEMS
Group 00 – Component Removal and Installation
Group 05 – Rear Differential and Input Quill
Group 10 – Final Drives
Group 15 – Rear PTO
Group 20 – Hydraulic Pump Drive
Group 25 – MFWD Clutch
Group 30 – Drivelines
Section 57 – MFWD AXLES
Group 00 – Component Removal and Installation
Group 05 – Final Drives
Group 10 – Axle Housing
Group 15 – Differential
Group 20 – Input Gear Train
Group 25 – Oscillation
Group 30 – Secondary Brake
Section 58 – INDEPENDENT LINK SUSPENSION™ AXLE
Group 00 – Component Removal and Installation
Group 05 – Controls
Group 10 – Final Drives
Group 15 – Drive Shafts
Group 20 – Brakes
Group 25 – Differential
Group 30 – Steering
Group 35 – Suspension
Section 60 – STEERING AND BRAKES
Group 05 – Steering Column
Group 10 – Steering Control Assembly
Group 15 – Steering Cylinders
Group 20 – Brake Valve
Group 25 – Brake Components
Group 30 – Trailer Brakes
Section 70 – HYDRAULICS
Group 00 – Component Removal and Installation
Group 05 – Hydraulic System Repair and Cleanup
Group 10 – Tandem Hydraulic Pump (Steering-Brakes-Charge)
Group 15 – Secondary Hydraulic Pump (Hitch-SCV)
Group 20 – Filter Bypass
Group 25 – Hitch Valve, Selective Control Valves, and Couplers
Group 30 – Hitch
Section 80 – MISCELLANEOUS
Group 05 – Hood
Group 10 – Front Axle (Two-Wheel Drive)
Group 15 – Wagon and Pick-Up Hitch
Section 90 – OPERATOR STATION
Group 00 – Component Removal and Installation
Group 05 – Heating, Ventilating, and Air Conditioning (HVAC)
Group 10 – Air Conditioning System
Group 15 – Air Suspension Seat
Group 20 – ACTIVE SEAT™
Group 25 – Armrest
Group 30 – Cab Door and Windshield
Section 99 – DEALER FABRICATED TOOLS
Group 05 – Fabricated Tools