Part of the John Deere Repair Manuals.
This is the complete John Deere factory repair manual for the 8120T, 8220T, 8320T, 8420T and 8520T track tractors. Across 1,015 pages it covers every major system on the machine: engine remove-and-rebuild, fuel injection and cooling, the PowerShift transmission and final drives, the full hydraulic circuit with pump and valve procedures, steering and track frame service, and the electrical system with harness and fault-code diagnostics. It is the same information a John Deere dealer technician uses, with the torque values, fluid capacities and special tool numbers called out so every repair is done to spec.
What's Inside This Repair Manual
| System | Pages | Key Topics |
|---|---|---|
| General Information | Safety, Specifications, Special Tools, Tightening Torques, Identification Numbers, Fuels and Lubricants | |
| Engine | Engine Remove and Install, Cylinder Head, Pistons and Rods, Crankshaft, Camshaft, Lubrication System | |
| Fuel and Cooling Systems | Fuel Injection, Fuel Filters, Air Intake, Radiator, Fan Drive, Coolant System, Turbocharger | |
| Electrical | Batteries, Alternator, Starting Motor, Lighting, Wiring Harness, Fuses and Relays, Instrumentation, Fault Code Diagnostics | |
| Transmission | PowerShift Transmission, Clutch Packs, Planetary Gear Sets, Oil Pump, Transmission Control | |
| Drive Systems | Differential, Final Drives, Track Drive Sprockets, PTO, Driveshafts | |
| Steering and Brakes | Steering Control Unit, Steering Cylinder, Steering Angle Sensors, Brakes, Parking Brake | |
| Hydraulics | Hydraulic Pump, Control Valves, Hitch Hydraulics, Selective Control Valves, Hydraulic Cylinders | |
| Miscellaneous | Frame, Drawbar, Ballast Weights, Accessories | |
| Operator Station | Cab, HVAC System, Controls and Pedals, Seat, Instrumentation Panel | |
| Track Frame and Components | Track Frame, Track Rails, Idlers, Rollers, Track Tension, Track Chains, Track Remove and Install | |
| Dealer Fabricated Tools | Special Tool Fabrication, Tool Specifications, Procedures |
Documents This Manual Refers To
The manufacturer cites these publications by number. We carry them:
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| 8220T, 8320T, 8420T, 8520T | ||
| Engine Displacement (8220T-8520T) | 9 L (549 in.3) | |
| All models | ||
| Rated Engine Speed | 2100 rpm | |
| Slow Idle Speed | 890-910 rpm | |
| Fuel Tank Capacity | 492 L (130 gal) | |
| Cooling System Capacity | 40 L (10.5 gal) | |
| Transmission and Hydraulics Capacity | 246 L (65 gal) including clean-oil reservoir | |
| Hydraulic System Maximum Pressure | 20,000 kPa (200 bar) (2900 psi) | |
| Hitch Lift Capacity (with Quick Coupler) | 6894 kg (15,200 lb) | |
| Front Frame-to-Transmission Cap Screws Torque | 430 N-m (317 lb-ft) | |
| Radiator Pressure Test | 80 kPa (0.8 bar) (12 psi) | |
| Radiator Cap Pressure Test | 60-80 kPa (0.6-0.8 bar) (9-12 psi) | |
| Electrical System | 12-volt, 200 amp alternator, dual 12-volt batteries in parallel | |
