Part of the Hyundai Repair Manuals.
All 665 pages of this Hyundai HL770-7A, HL770XTD-7A service manual PDF point at one job: keeping both wheel loader variants running to factory spec. Inside you get complete electrical circuit diagrams with connector pinouts, hydraulic schematics for the brake, steering, and work equipment circuits, and full transmission fault code tables for the electro-hydraulic shift control. Step-by-step teardown procedures cover the torque converter, both Volvo and ZF axles, and the differential, right down to brake hydraulics leakage testing. The main pump tops out at 150 kgf/cm² delivery pressure; torque the engine mounting bolts to 100 ± 15 kgf·m and change the hydraulic oil filter every 250 operating hours. A loader sitting dead costs you money every shift. Bookmarked and searchable by keyword; open it on a phone or tablet and walk straight to the machine.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| General | 11-36 | Safety Hints, Specifications, Operational Checkout Record Sheet |
| Engine | 37-44 | Structure and Function |
| Power Train System Overview and Torque Converter | 45-49 | Power Train Component Overview, Torque Converter Function, Hydrodynamic Torque Converter |
| Transmission Layout and Operation | 50-66 | Transmission Layout, Forward and Reverse Gear Operation, Electro-Hydraulic Shift Control, Gear Selector, Aeb Mode |
| Transmission Fault Codes and Troubleshooting | 67-112 | Engine Fault Codes, Transmission Fault Codes, Operating Modes, Axle Operation, Differential Operation, Final Drive Section |
| Power Train Operational Checks and Troubleshooting | 113-123 | Power Train Operational Checks, Transmission Troubleshooting, Differential and Axle Troubleshooting, Drive Line Troubleshooting |
| Transmission Tests, Adjustments, and Disassembly | 124-218 | Clutch Cut-Off Pressure Switch Test, Transmission Measuring Points, Control Valve Disassembly and Assembly, Transmission Disassembly and Assembly |
| Axle Disassembly, Assembly, and Testing | 219-363 | Volvo Axle Disassembly and Assembly, Zf Axle Disassembly and Assembly, Brake Tube Disassembly and Assembly, Differential Assembly, Brake Hydraulics Leakage Test |
| Brake System | 364-411 | Structure and Function, Operational Checks and Troubleshooting, Tests and Adjustments, Disassembly and Assembly |
| Steering System | 412-509 | Structure and Function, Operational Checks and Troubleshooting, Tests and Adjustments, Disassembly and Assembly |
| Work Equipment | 510-591 | Structure and Function, Operational Checks and Troubleshooting, Tests and Adjustments, Disassembly and Assembly |
| Electrical System | 592-665 | Component Location, Electrical Circuit, Monitoring System, Electrical Component Specification, Connectors, Troubleshooting |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Engine mounting bolt, nut(Rubber, 2EA) | 100 ± 15 kgf·m | p. 30 |
| Inductive transmitter n-Engine(9) setting dimension X | 0.5 +0.3 mm | p. 228 |
| Main pump maximum delivery pressure | 150 kgf/cm² | p. 372 |
| Hydraulic oil filter replacement interval | 250 operating hours | p. 567 |
| Throttle check valve in PP-connection tightening torque | 1 ± 0.3 kgf·m | p. 469 |
| Steering unit mounting bolt | 6.9 ± 1.4 kgf·m | p. 30 |
| Center pivot pin bearing serviceable limit clearance | 0.8 mm | p. 507 |
| Fuel filter replacement interval | 250 operating hours | p. 567 |
| Transmission oil overheating warning temperature | 107°C | p. 614 |
| Engine Oil Quantity | 23 L | p. 27 |
| Main Relief Valve Pressure | 210 kgf/cm2 | p. 28 |
| Engine High Idling Speed | 2200 rpm | p. 27 |
