Gross Power 173 HP
Engine Model Cat C4.4 ACERT
Gross Power - 1,800 rpm 173 HP

Operating Weight 33800 lb
Counterweight N/A
Operating Weight - Without Grapple 33800 lb

Operating Specifications
Knuckleboom Length 32 ft
Swing Speed 11 r/min
Maximum Reach - Standard Boom 32 ft
Note *Theoretical
Swing Bearing - Diameter - Ball Path 43.5 in
Swing Torque* 49173 ft·lbf
Tail Swing 106 in

Service Refill Capacities
Hydraulic Tank 80 gal (US)
Fuel Tank 100 gal (US)
Cooling System 7.5 gal (US)
Engine Oil 2.1 gal (US)
Swing Drive 1 gal (US)

Hydraulic System
Cylinders - Main one
Cylinders - Stabilizers four
Cylinders - Stick one
Hydraulic Oil Flow at 1,800 rpm 230/174 L/min (60/46 gal/min)
Hydraulic Pressure - Swing 3625 psi
Hydraulic Pressure - System 3625 psi

Stabilizer Pad Size 508 × 711 mm (20 × 28 in)
Stabilizer Reach Below Grade 17 in
Stabilizer Spread - Maximum Down Reach 166.8 in
Height - Top of Cab 157.6 in
Stabilizer Spread - Grade 187.3 in

OFPS OFPS cab meets SAE J2267

Shipping Dimensions - Mounted Trailer
Height 157.6 in
Width 101.3 in

Note 559D dimensions are on non-suspension trailer.

GLK Series Grapples - GLK48
Area (tip to tip) 3 ft²
Close 4.5 in
Height - Open - Excluding Rotation 45.1 in
Height - Open - Including Rotation 66 in
Note All specifications are approximate.
Open 48 in
Weight - Excluding Rotation 1407 lb
Weight - Including Rotation 1907 lb

GLK Series Grapples - GLK55
Area (tip to tip) 3.8 ft²
Close 5 in
Height - Open - Excluding Rotation 46.7 in
Height - Open - Including Rotation 68 in
Note All specifications are approximate.
Open 54 in
Weight - Excluding Rotation 1411 lb
Weight - Including Rotation 1911 lb

Service Refill Capacities
DEF Tank 5 gal (US)


  • The Cat® C4.4 ACERT™ U.S. EPA Tier 4 Final engine provides equivalent power (129.3 kW/173 hp) and optimized performance compared to C Series while minimizing overall fluid consumption
  • Advanced controls manage pump and engine interface to optimize performance and fuel efficiency
  • Leading hydraulic multi-functioning capability enables operator to lift, swing, and rotate grapple simultaneously without impairing performance


  • Auto idle minimizes fuel consumption when machine is on and not actively working
  • High capacity cooling system only pulls in cool external air to maximize efficiency
  • Electrically controlled variable speed fan is modulated to provide cooling only as required, reducing fluid consumption


  • Smooth hydraulic controls and superior balance provide market leading comfort and controllability
  • High capacity HVAC system provides dependable cooling and heating for maximum comfort
  • Improved stabilizer controls to equalize stabilizer actuation resulting in optimized uniformity of footing in varying ground conditions


  • Stabilizer movement alarm alerts bystanders of stabilizer movement
  • Pilot enable alarm alerts bystanders when pilot function is engaged
  • Ground level access of engine, fuel, pilot, and case drain filters as well as electrical service box


  • Reinforced fabricated booms with optimized cross sections designed to withstand heavy side-to-side delimbing applications and maximize lift capability
  • Field proven cooling system keeps engine and robust hydraulic system cool, extending component life
  • Larger diameter pins feature heavy-duty plating for improved durability and excluder seals to retain grease and keep free of SP contaminant


  • Single cylinder main boom has fewer parts to service than traditional dual cylinder lift system
  • Standard electric fill pump for hydraulic oil is at ground level for safe, easy service
  • Hinged doors provide industry-leading access to core components, daily check points, and service locations

Cat Work Tools

  • Optimized Cat XT™-6 ToughGuard™ hose routings on GLK Series grapple designed to minimize loosening of fittings and improve hose life
  • Larger GLK Series cylinder pins and bushings reduce bearing stress by 25 percent
  • Available now in both a TW “Tapered Wide” and SN “Straight Narrow,” the GLK Series grapple is suitable for additional applications
  • Standard hold valves on GLK Series log grapples improve log retention
  • GLK Series grapples feature optional three port swivel which allows mounting of grapple saw
  • DLK426 delimber knives now have larger diameter pins that reduce bearing stress by 12 percent