Cat GP55N Specifications
The Caterpillar GP55N is a high-capacity 5.5-ton (5,500
kg / 12,125 lb) pneumatic-tire LPG/petrol forklift engineered for demanding
indoor-outdoor industrial applications requiring strong low-RPM torque, stable
load-handling behavior, long-duty cycle reliability, and heavy-frame structural
integrity. As one of the largest models in the Caterpillar GPN-Series, the GP55N
is designed for continuous multi-shift environments in steel fabrication yards,
large distribution depots, manufacturing plants, lumber and timber operations,
freight terminals, ports, and heavy material-handling sites.
The model supports two spark-ignition engines: the Nissan GK45K, a highly
durable 4.5-liter industrial V6, and the PSI 4X, a 4.3-liter industrial V6 LPG
engine optimized for low emissions, excellent throttle response, and strong
torque curves. The GP55N integrates a reinforced heavy-gauge steel chassis,
high-capacity mast assemblies, industrial powershift transmission, wide
pneumatic tires, a load-sensing hydraulic system, and a stable counterweight
configuration optimized for high-load center handling.
The operator environment emphasizes ergonomic control, reduced vibration, clear
forward visibility, low-effort hydraulic levers, an adjustable suspension seat,
and wide-area foot space. Technicians appreciate the GP55N’s
maintenance-friendly design including wide-opening hood covers, centralized
filters, long-life ignition components, durable wiring protection, logical
hydraulic routing, and simplified diagnostic access.
Two industrial
spark-ignition engines are offered:
- Nissan GK45K - 4.5-liter V6 industrial LPG/petrol engine
- PSI 4X - 4.3-liter V6 industrial LPG engine
Nissan GK45K - Technical Specifications
- Type: V6, 4-stroke, spark-ignition
- Displacement: approx. 4.5 L
- Power output: approx. 63-75 kW (84-100 hp) @ 2,400-2,600 rpm
- Peak torque: approx. 250-310 Nm (184-229 lb-ft) @ 1,600-1,800 rpm
- Fuel: LPG or gasoline (depending on market)
- Fuel system: electronic fuel injection
- Aspiration: naturally aspirated
- Idle speed: approx. 650-750 rpm
- Known characteristics: smooth torque rise, reliable performance, low vibration
PSI 4X - Technical Specifications
- Type: V6, 4-stroke, spark-ignition LPG engine
- Displacement: approx. 4.3 L
- Power output: approx. 70-82 kW (94-110 hp) @ 2,400-2,600 rpm
- Peak torque: approx. 270-330 Nm (199-243 lb-ft) @ 1,600-1,800 rpm
- Fuel system: electronic multi-point LPG injection
- Aspiration: naturally aspirated
- Known characteristics: strong low-RPM torque, low emissions, excellent
throttle response
Lubrication System (Both Engines):
- Type: full-pressure lubrication
- Pump: internal gear pump
- Oil capacity: approx. 5.5-7.0 L (5.8-7.4 qt)
- Operating pressure: approx. 250-400 kPa (36-58 psi)
- Recommended oil: SAE 10W-30 or 15W-40
- Filtration: spin-on full-flow oil filter
Cooling System (Both Engines):
- Cooling type: liquid-cooled
- Capacity: approx. 10-12 L (10.5-12.7 qt)
- Thermostat opening: approx. 82°C (180°F)
- Fully open: approx. 95°C (203°F)
- Radiator: heavy-duty fin-tube core
- Fan: belt-driven mechanical
- Water pump: centrifugal belt-driven
- System pressure: approx. 90-110 kPa (13-16 psi).
Transmission:
- Type: heavy-duty industrial powershift
- Speeds: 1-2 forward / 1-2 reverse
- Direction control: electric-over-hydraulic shuttle
- Travel speed (unladen): approx. 18-20 km/h (11-12 mph)
- Travel speed (laden): approx. 15-18 km/h (9-11 mph)
- Fluid capacity: approx. 12-16 L (12.7-16.9 qt)
- Fluid type: Dexron III ATF or dedicated powershift oil
- Cooling: oil-to-air cooler
Front Drive Axle:
- Type: reinforced rigid steel axle
- Differential: bevel-gear industrial differential
- Capacity: approx. 6-7.5 L (6.3-7.9 qt)
- Lubricant: SAE 80W-90
Rear Steer Axle:
- Type: oscillating center-pivot
- Oscillation range: approx. ±8-10 degrees
- Capacity: approx. 1.0-1.5 L
Braking System:
- Service brakes: hydraulic drum brakes
- Parking brake: mechanical lever-operated
- Optional: oil-cooled wet-disc brakes (regional option).
- Operating voltage: 12 V
- Battery capacity: approx. 100-140 Ah
- Alternator output: approx. 60-90 A
- Starter motor: approx. 2.5-3.0 kW
- Wiring harness: abrasion-protected, sealed connectors
Dashboard indicators:
- oil pressure
- coolant temperature
- charging system
- LPG level/fuel status
- hour meter
- parking brake indicator.
Drive
configuration:
- Front-wheel drive
- Rear-wheel steering
- Drive type: 2WD
Tire Configuration (Pneumatic Standard):
- Front: approx. 8.25-15
- Rear: approx. 7.00-12
- Optional: solid pneumatic / non-marking tires
Chassis Construction:
- Fully welded high-strength steel frame
- Large integrated counterweight
- Reinforced overhead guard
- Anti-slip steps
- Rubber-mounted engine supports
- Protected hydraulic/electrical routing
Steering:
- Type: fully hydrostatic steering
- Pump flow: approx. 7-15 L/min (1.8-4.0 gpm)
- Rear axle: center-pivot oscillating
- Steering cylinder: double-acting
- Turning radius: approx. 2.7-2.9 m (106-114 in).
- Pump type: engine-driven gear pump
- Flow rate: approx. 80-110 L/min (21-29 gpm)
- Maximum pressure: approx. 18-21 MPa (2,610-3,050 psi)
- Hydraulic reservoir: approx. 40-55 L (42-58 qt)
- Oil type: ISO VG 32 or VG 46
- Lift cylinders: dual heavy-duty double-acting
- Tilt cylinders: dual cushioning design
- Main valve: proportional spool or load-sensing configuration
Optional Hydraulic Attachments:
- Side-shift
- Fork-positioner
- Rotator
- Bale/drum clamp
- Paper roll clamp
- Push-pull (slip-sheet).
| Service Refill Capacities |
- Engine oil: 5.5-7.0 L
- Cooling system: 10-12 L
- Transmission: 12-16 L
- Drive axle: 6-7.5 L
- Steer axle: 1-1.5 L
- Hydraulic system: 40-55 L
Mast Types:
- Simplex (1-stage)
- Duplex (2-stage)
- Triplex (3-stage full free-lift)
Lift Heights:
- Simplex: approx. 2.5-3.5 m
- Duplex: approx. 3.0-4.5 m
- Triplex: approx. 4.5-6.0 m
Free Lift: approx. 80-1,000 mm
Carriage Width: approx. 1,200-1,350 mm (47-53 in)
Fork Options:
- Standard: 1,070 mm (42 in) or 1,220 mm (48 in)
- Optional: 914-1,829 mm (36-72 in)
- Fork width: 100-150 mm
- Fork thickness: 40-55 mm
- ITA class: Class III or Class IV.
- Rated capacity: 5,500 kg (12,125 lb)
- Load center: 500-600 mm (20-24 in)
Factors requiring capacity derating:
- high lift heights
- fork extensions
- side-shift / fork-positioner use
- off-center loads
- uneven terrain or inclines.
- Lift speed (unladen): approx. 0.45-0.60 m/s
- Lift speed (laden): approx. 0.28-0.45 m/s
- Lowering speed: approx. 110-170 ft/min
- Gradeability (unladen): approx. 20-30%
- Gradeability (laden): approx. 15-22%
- Drawbar pull: approx. 24,000-32,000 N (5,395-7,190 lbf).
- Overall length to fork face: approx. 3.2-3.5 m
(126-138 in)
- Overall width: approx. 1.45-1.65 m (57-65 in)
- Overhead guard height: approx. 2.2-2.3 m (87-91 in)
- Wheelbase: approx. 2.0-2.2 m (79-87 in)
- Ground clearance: approx. 180-220 mm (7-8.7 in)
- Turning radius: approx. 2.7-2.9 m
- Aisle width (1000x1200 pallet): approx. 4.2-4.6 m
- Maximum fork height: 2.5-6.0 m
- Free lift: approx. 80-1,000 mm
- Fork lengths: 36-72 in
- Operating weight: approx. 7,000-8,500 kg (15,432-18,739 lb)
- Counterweight mass: approx. 3,200-4,200 kg (7,055-9,259 lb).
250-Hour Service:
- Replace engine oil and filter
- Clean radiator stack
- Lubricate mast and steer axle joints
- Inspect air filter
500-Hour Service:
- Replace transmission fluid
- Inspect axle seals
- Clean hydraulic suction strainer
1,000-Hour Service:
- Replace hydraulic fluid and filters
- Replace coolant
- Inspect hoses, wiring, and cylinder seals
2,000-Hour Service:
- Full driveline inspection
- Steering geometry evaluation
- Mast structural integrity check.
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| Telehandlers Specifications |
| Front-End Loader Specifications |