A transaxle that starts slipping under load, or an ignition that drops the truck dead mid-aisle, is what the 895-page Clark GCS service manual PDF (OEM number SM520) was written to settle. Covering the GCS, GCX, DCS, GPX, GPS and DPS series, this factory book runs from General Information through the Uprights section. Electrical system wiring diagrams trace ignition and charging circuits back to the battery, while the hydraulic chapter walks the sump fluid and filter change through to a full main pump overhaul. Main relief pressure is tuned to capacity, 2300-2400 psi on GC(P)S(X) 17-20 trucks. Set idle at 650 rpm nominal on both the 4G54 and TM(D)27 engines, with 600 to 700 rpm as the acceptable band, and check that Group 31 battery for its rated 625 amps at 0F. A guessed brake pressure puts a loaded truck somewhere it should not be. Bookmarked, searchable, yours once you buy it.
What's Inside This Clark GCS, GPS Series Manual
| System | Pages | Key Topics |
|---|
| General Information | 5-14 | Safe Maintenance Practices, Product Identification |
| Specifications | 15-36 | Product Specification Changes, Service Specifications |
| Planned Maintenance | 37-63 | PM Schedules, Planned Maintenance Procedures |
| Engine | 64-188 | Engine Troubleshooting, Engine Tune-Up, Engine Adjustments |
| Fuel System | 189-286 | Fuel Systems Maintenance, LPG Fuel System |
| Electrical System | 287-400 | Electrical System Wiring, Ignition System Maintenance |
| Transaxle | 401-646 | Transaxle Maintenance, Transaxle Overhaul General Procedures |
| Brakes and Inching System | 647-685 | Service Brake and Inching Systems, Brake and Inching System Type 1 |
| Steering System | 686-766 | Steering Column Removal and Installation, Steer Axles |
| Hydraulic System | 767-812 | Hydraulic Sump Fluid and Filter Change, Main Hydraulic Pump Overhaul |
| Wheels and Tires | 813-833 | Cushion Tire and Wheel Maintenance, Pneumatic Tire and Wheel Maintenance |
| Counterweight and Chassis | 834-850 | Counterweight Maintenance, Chassis Components |
| Uprights | 851-872 | Upright Maintenance, High Visibility Standard Upright |
Quick Reference Specifications
| Specification | Value | Page |
|---|
| G54, D176GA |
| Battery 1 Cold Crank Current | 420 amps @ 0°F | p. 18 |
| TM27 |
| Battery 2 Cold Crank Current | 320 amps @ 0°F | p. 18 |
| 4G54 Engine |
| Idle Speed Setting | 650 rpm, nominal (Range: 600-700 rpm) | p. 136 |
| All Models |
| 4G54 Engine Idle Speed | 650 rpm (600-700 rpm) | p. 83 |
| TM(D)27 Engine Idle Speed | 650 rpm (600-700 rpm) | p. 83 |
| Steering cylinder thru fastener nut torque | 40-45 Nm (30-33 lbf.ft) | p. 766 |
| 4G54 |
| Engine Oil Capacity (4G54) | 4.5L | p. 20 |
| Cooling System Capacity (4G54) | 8.5L | p. 20 |
| TM27/TMD27 |
| Engine Oil Capacity (TM27/TMD27) | 6.6L | p. 21 |
| Cooling System Capacity (TM27/TMD27) | 8.5L | p. 21 |
| D176GA |
| Engine Oil Capacity (D176GA) | 4.7L | p. 22 |
| Cooling System Capacity (D176GA) | 8.5L | p. 22 |
