555D Wheel Skidder

555D Wheel Skidder

Building on Caterpillar’s 40+ years’ experience designing and manufacturing skidders, the Cat® D Series Wheel Skidder delivers more productivity at lower operating cost. Get more wood to the landing faster in a stable machine with a roomy, comfortable environment for the operator. Advanced hydraulics speed up multi-functioning and cycle times and give you more lift capacity. The D Series runs cool and is designed to keep debris from collecting inside the machine. Tilting cab and other access points cut the time needed for daily maintenance and servicing.

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Engine

The Cat C7.1 ACERT™ engine is designed to deliver more power than ever before, while still achieving the highest levels of total fluid efficiency, reliability and durability.

The C7.1 ACERT engine meets U.S. EPA Tier 4 Final and EU Stage IV emission standards using a blend of technologies to optimize performance, whatever the conditions. The Selective Catalytic Reduction (SCR), Exhaust Gas Recirculation (EGR) and Diesel Oxidation Catalyst (DOC) systems effectively remove NOx gasses from the exhaust, while a fully passive, service-free Diesel Particulate Filter (DPF) removes soot and other particulates. All Cat C7.1 ACERT emissions technologies are designed to be transparent, so you are free to concentrate on the job at hand.

The High Pressure Common Rail Fuel System provides precise and efficient combustion, allowing for maximum performance improved fuel efficiency and enhanced reliability. Series turbochargers provide extra power when needed. The engine is designed for maximum uptime and reduced operating costs, with world-class support from the Cat dealer network.

Industry leading integration and engineering support is at the heart of everything we do. The Cat C7.1 ACERT engine is fine-tuned to work seamlessly with machine control systems, optimizing the engine for demanding work cycles.

With a durable design and long life, the C7.1 ACERT delivers better fuel economy, with minimized maintenance costs, while still providing the same great power and response you expect.

Cooling System

The high capacity cooling system and on-demand hydraulically driven reversing fan keep the machine running at the proper operating temperature, optimizing performance, durability and fuel efficiency. The system, designed to meet the cooling requirements of the 555D, is common to all models, boosting fuel efficiency and capacity in the smaller models.

Access all components

The system is arranged in two panels. The engine radiator and coolers for hydraulic oil and fuel are stationary, and a swing-out hinged panel houses the air conditioner condenser and air-to-air after cooler (ATAAC). The transmission cooler is a water-to-oil type using engine coolant for cooling. All components are within easy reach and the cooling system can be cleaned from both sides. The fan shroud can be easily removed for increased service access below the cooling system.

Cool and clean

The cross-flow configuration and compartmentalization of the engine and cooling system maximize efficiency and reduce debris collection. The fan shroud and baffling requires cool ambient air to be pulled in from the side — not from the engine compartment. Air is exhausted on the opposite side. This prevents hot air from circulating and debris from collecting in the engine compartment. Fin spacing is coarse to allow debris to pass through more easily and reduce plugging.

Reversing fan

The oversized fan spins at a slower speed, only as fast as needed to maintain proper operating temperatures. In colder weather or when the machine is first started the fan spins more slowly to conserve power and fuel and reduce noise. The fan automatically reverses every 20 minutes of run time. The operator can activate reversal between cycles through a manual override.

Power Train

Power to the ground is an advantage of the Cat D Series. The axles are designed specifically for the skidder application and the gear ratios cause the power to be generated in the axles reducing torque in the transmission and drivelines extending their life. Both drawbar performance and durability are improved.

Service/parking brakes

The service brake components are housed inside the axles, protecting them from dirt, dust and moisture. An inline parking brake is spring activated and hydraulically released.

Six-speed transmission

The field proven Cat countershaft powershift transmission easily matches engine power to the load size and ground conditions. The D Series gears are more evenly distributed in the working range to maximize performance in tough terrain and ground conditions.

Electronic Clutch Pressure Control

Electronic Clutch Pressure Control (ECPC) provides a valve for each clutch in the transmission to regulate and modulate the individual clutches based on current operating conditions and operator input. The result is smoother, faster, more efficient gear changes maximizing performance, durability and operator comfort.

Lock-up torque converter

The lock-up torque converter allows the machine to ease smoothly into a start when the skidder has a heavy load in the grapple, which is easier on the tires and chains. Then, depending on ground speed and conditions, the lock-up clutch automatically engages and the transmission goes into direct drive for high efficiency hauling and up to 15% faster travel speeds in the same gear.

Independent front/rear differentials

The D Series is easy to maneuver even in dense woods and slippery or steep conditions. In normal operation, all four wheels move independently. In poor ground conditions, the independent front and rear differential locks can be engaged separately for better pulling performance and to maintain maneuverability. The locks are hydraulically actuated and can be engaged on the go.

Hydraulics

The new hydraulic system gives the D Series more speed, increased multifunctioning capability and greater lift capacity. This efficient load sense system with variable displacement pump continually monitors hydraulic power requirements and provides power based on demand to save fuel.

Cat hoses

Cat ToughGuard™ hoses increase hose life in the grapple, arch, boom and across the hitch. The ToughGuard cover consists of a layer of UHMW polyethylene bonded to the rubber cover, providing exceptional abrasion resistance. O-ring face seals assure rocksolid connections that maintain pressure and reduce oil leaks, particularly along the arch and boom and through the center hitch.

Fast cycle times

While steering has full priority, the new hydraulic system allows plenty of flow to continue to the main control valve. You can steer, back up and activate arch, boom and grapple functions at the same time. Cycle times are significantly faster increasing productivity.

More lift

Job sites today demand more of the skidder than delivering harvested trees to the landing. The skidder is often the workhorse called on to move the knuckeboom loaders. Hydraulic system pressure boosts of 15% for the 525D and 535D and 23% for the 545D and 555D, matched to the boom length, increase the lift capacity of the D Series. You can more quickly move your loaders to a new job site and get on with the work.

Auto-grab

The auto-grab feature monitors tong pressure and adjusts as needed to securely hold grapple loads while skidding. For more secure transport of heavy loads, auto-grab pressures are higher in the D Series as a result of the increased system pressures. A switch on the right-hand joystick activates this feature.

Electrohydraulic controls

The electrohydraulic grapple, blade and winch controls give you more precision operating the skidder while eliminating hydraulic pilot lines in the cab.

Structures

Robust frames provide a solid foundation for a machine designed to provide long life. Every structure was engineered for durability and verified through lab and field tests.

Extra-strength fenders

The fenders extend tire life by providing maximum coverage in both grapple and cable skidding applications. The cable fenders continue to be the best in the market. The angle of the grapple fender support plates provide additional rigidity. Support structures between the fender and the rear frame provide even greater support.

Strong frames

Front and rear frames are robot welded to ensure the highest level of quality and durability. Box section construction is utilized to support bending and twisting forces created by heavy loads. Field proven steering cylinder mounts distribute forces over a large area to maximize life. The solid steel nose of the D Series is built to withstand the toughest applications.

Field-proven center hitch

The field-proven center hitch design features large dual tapered roller bearings in both the upper and lower hitch with 3 in. (76 mm) diameter pins providing maximum durability. The spread between the upper and lower hitch pins reduce horizontal loading on the pins and bearings for greater durability and extended life. The extra room also increases hydraulic hose clearance and makes hose routing easier.

Pin-mounted blade

The pin-mounted blade in the D Series is more durable and feature short, large diameter pins. The industries only blade with bolt-on cutting edges made of abrasion-resistant, heat-treated steel significantly increases the life of the blade. Also, the angle of the blade to the ground when pushing dirt or debris is optimized for smoother, more efficient blading.

Strengthened bottom guarding

Bottom guards, including guarding on the rear axle, protect the underside. The increased rigidity of the lower frame provides extra support to the bottom guarding to prevent damage from riding over stumps and rocks.

Arches and Boom

Box-section construction was used in the arch and boom designs to transfer heavy loads efficiently into the main frames. The arch gate is integrated into the arch and comes with a bolt-on fairlead roller assembly for skidders ordered with a winch, or a bolt-on guard, for skidders not equipped with a winch.

The dual function arch and boom is available on all models while the single function arch is available on the 525D and 535D. The cable arch is available on all except the 555D.

Grapple

The 360° continuous rotation grapple features box-section construction and threaded grapple tong pins that maximize structural integrity. Additional internal support and around the grapple tong pin increases rigidity while service panels provide access to all grapple head components.

The grapple tongs are shaped to roll trees up quickly for a fully loaded grapple. Tight clamping forces and raised edges on the tongs keep the drag secure during transport while providing extended wear life. Tongs have replaceable wear tips and are reinforced internally to support twisting loads. Internal welding in high wear areas increases the durability and extends the life of the tongs.

Winches

Logging and retrieval winches are available as options. Both are hydraulically driven, have the same pulling power and feature friction style clutches for increased durability and functionality. Both the retrieval and logging winches are operated by a joystick for more control over the reeling speed.

Retrieval

The retrieval winch runs off the skidder’s main hydraulic pump and is designed to support machine and truck retrieval. All single or dual function models can be equipped with a retrieval winch.

Logging

All 525D, 535D and 545D single or dual function models can be equipped with a logging winch for more versatility in regions where the ability to do both grapple and cable skidding is needed. The logging winch is standard in all cable arch configurations for production cable logging applications. A dedicated hydrostat pump and internal gearing changes boost the speed of the logging winch to optimize productivity in cable logging applications.

Operator Station

The new D Series cab is roomy, quiet and cool with great visibility, especially out the back.

Clear monitor display

Check status of the machine’s systems with the clean and clear monitor display:

  • Check status of the machine’s systems with the clean and clear monitor display:
  • Indicator lights provide additional information such as auto-grab, torque converter lock-up, and differential lock engagement.
  • If a system problem occurs, the monitor will display an easy-to-understand text explanation, along with applicable fault codes.
  • If a condition requires immediate action, a warning buzzer will sound. The operator must acknowledge the warning to turn off the alarm. Depending on how serious the warning, the alarm will continue to sound until the condition is addressed.
  • Everything the system does is recorded in the system log for monitoring machine health and operator activity.

Smooth ride

The cab offers plenty of legroom for tall operators and space to store tools and personal items. The cab is isolation-mounted to the skidder frame to minimize vibration and positioned between the axles for the most comfortable ride possible, no bucking.

Pressurized cab

The cab is pressurized and sealed (with side windows closed) for efficient heating and cooling and sound control. Tight door and window casings also keep out dust. The sealed cab keeps engine and job site noise low.

Cat Comfort Seat

The standard Cat Comfort Seat swivels 30° to the right so you can watch skidder and grapple operations. Beyond adjustments for seat and armrest position, recline and lumbar, the high back seat can be adjusted to accommodate height and weight and ride firmness preferences to reduce fatigue. The grapple is controlled through the seat-mounted joystick. You can rest your forearm on the armrest and have full control in your hand. Steering with the quarter-turn steering wheel is smooth. The steering column tilts and telescopes to your preferred position.

High capacity HVAC

The durable, high capacity HVAC (heating, ventilation, and air conditioning) system provides dependable cooling and heating. Vents in front and on both sides can be directed toward the operator or the windows.

360˚ visibility

A clean three-piece front windshield and tall, wrap-around rear windows give you a 360˚ view, including the corners of the blade and winch drum. The engine air precleaner has been moved under the hood and the exhaust stack significantly shortened to increase visibility out the front windshield. The engine enclosure and arch and booms are black to reduce glare during night operations.

Other cab features include two large cup holders, one 12-volt power point for cell phone chargers etc., two coat hooks, AM/FM/ CD/Sirius satellite radio package with Bluetooth, USB and auxiliary inputs.

Serviceability

Serviceability of the D Series is significantly improved with the tilting cab, redesigned grapple head and improved hose routings. Keeping the machine clean is easy, too.

Straightforward Tier 4 Final engine maintenance:

  • Any commercial DEF that meets the ISO 22241 specification can be used in Cat SCR equipped engines. DEF can be purchased at Cat dealers.
  • The extended life diesel particulate filter (DPF) was designed for the life of the engine and has a unique remaining life feature which can be checked by your local Cat dealer.
  • The filter assembly for the pump electronics tank unit (PETU), the tank for onboard DEF storage, must be replaced every 5,000 hours.

Tilting cab

The tilting cab with field proven tilting pins provides access to components under the cab. Bolt-on panels around the base of the cab and removable steps provide even more access.

Debris management

The cross flow configuration and compartmentalization of the engine and cooling system reduce debris collection around the engine, so less time is needed for cleaning. The cooling system pulls external air in the side — not through the engine compartment — and exhausts it on the opposite side.

Smart hose routing

Hoses from the arch to the boom take a lot of abuse from rubbing against the arch and boom of dual function machines. Guarding on the arch and boom protect the hoses. Hoses across the joint are short, so replacement is a low cost fix. Also, stiffness of the Cat XT hoses keep them suspended across the arch and boom joint rather than rubbing against the steel. Center hitch hoses are bulkheaded to optimize serviceability access and durability.

Steering cylinder access

In some skidders, it is not easy to get to the steering cylinders. With the D Series, you just unbolt the cab steps to access the steering cylinders.

Brake release

The parking brake is normally released hydraulically; however, grease injected from a simple valve near the main control valve will release the parking brake manually if needed.

Grapple head servicing

The new grapple head is designed for greater durability and serviceability. Components and fittings are accessed through the new service panels on both sides of the head and above the grapple tong cylinders.

Other highlights include:

  • Fuel fill at ground level.
  • Up to 500-hour engine oil change intervals, pending oil sampling recommendation, keep maintenance costs low.
  • Electrical harnesses are bulkheaded before entering the cab, improving cab pressurization and reducing dust and noise.
  • Access to the main control valve is on the rear frame of the skidder.
  • The engine is serviced at ground level from a single side.
  • Hinged panels provide access to other daily service points, and hinged belly pans allow water to drain when pressure washing the skidder with the cab tilted.
  • Large hinged mesh screens over the door windows protect you when the sliding windows are open. They swing out to remove debris.

Customer Support

Caterpillar is known the world over for the quality of customer support from its dealer network – the industry’s best. No matter where you are, the expertise of a Cat dealer is always nearby. Your local Cat dealer is your forestry consultant who can recommend the machines, work tools and services to maximize your operation and provide the support to keep you at top productivity.

  • 24-hour parts availability, where and when you need them, to minimize expensive downtime.
  • Remanufactured parts that carry the same warranty as new parts at a reduced cost.
  • Operator training to get the most out of your Cat equipment.
  • Field services to provide on-site help when needed.
  • Timely repair and replacement services.
  • Customer Support Agreements to lower your operating costs.
  • State-of-the-art diagnostic programs, such as S·O·SSM oil analysis, inspection services and trend reporting to help avoid unscheduled repairs.
  • Financing programs for buying, renting or leasing Cat equipment.
  • Cat Financial Commercial Account, a fast and convenient way to pay for or rent anything offered at any Cat dealer or The Cat Rental Store.
  • Cat Insurance to cover equipment losses from theft, collision, flood, upset or overturn, fire, vandalism and more.
  • Product Link™ to manage your equipment fleet through remote monitoring.
  • Cat Certified Rebuild to get a second life from your equipment.

Sustainability

The D Series wheel skidders are designed to maximize efficiency and productivity while conserving natural resources.

  • The C7.1 ACERT engine meets U.S. EPA Tier 4 Final and EU Stage IV emission standards.
  • The D Series is more fuel efficient which means reduced emissions per unit of work performed.
  • Fewer parts and longer component life, less fuel and fluids, means less to replace and less to dispose.
  • Major structures and components are built to be rebuilt, reducing waste and replacement costs.

Integrated Technologies

Caterpillar offers solutions to help you work smarter.

Machine Troubleshooting

The D Series skidders come with a machine troubleshooting feature that allows the operator to drill down and pinpoint the root cause of a problem, reducing the need for service calls and holding down costs.

Cat Product Link

Cat Product Link, Caterpillar’s machine monitoring system, is standard on all D Series skidders. When installed at the factory, the system comes with a free three-year subscription to VisionLink®, the user interface.

Product Link is an advanced — but user friendly — remote monitoring technology for equipment. With Product Link, you know where your skidder is, what it’s doing and how it’s performing. Armed with this information you can maximize efficiency and lower operating costs.

Product Link is integrated with the Electronic Control Modules (ECMs) on Cat equipment to collect and deliver valuable information.

Because logging sites tend to be in remote areas, information will be transmitted via satellite for more consistent communications.

You will have remote access to information over the web at any time and any place. With Product Link you can:

  • Know the location and status of your D Series skidder, including alerts if it is moved without your knowledge
  • Track fuel use and idle time
  • Monitor efficiency and health, including fault codes
  • Access fluid analyses results and online parts ordering
  • Access model-specific daily safety and maintenance inspection checklists.

Safety

Safety is critical in the woods and a number of unique safety features have been designed into the D Series skidders, including:

  • Ground level fueling
  • Ground level daily maintenance
  • ROPS/FOPS/OPS certified cab with tough Lexan windows
  • Weight distribution and longer wheel base that maximize stability
  • Additional mesh screen guarding on side windows
  • Pressurized operator station for a clean, quiet environment
  • 360° visibility of the work area from the cab
  • Safe and secure access into and out of the cab with grab handles and steps with gripper surface
  • Forestry-duty cooling packages
  • Debris management includes reversing fan to keep debris from clogging airflow inlets, segregated cooling package that allows debris to pass through and not collect or migrate to the engine compartment
  • Ground level machine kill switch
  • Halogen working lights

Engine

Gross Power
275hp
Engine Model
Cat C7.1 ACERT™
Displacement
428in3
Bore
4.13in
Stroke
5.31in
Max Torque @ Rated Speed
922 N-m at 1400 RPM
Derating Altitude
9843ft
Electrical System
24V
Battery - Quantity
2
Battery - Volts
12V
Battery - Capacity
950 CCA
Number of Cylinders
6

Dimensions

Weight - Dual Function
47488lb
Ground level to axle center line*
33.2in
Overall length - Dual Function
354.6in
Ground Clearance*
21.7in
Blade lift height*
56.1in
Blade dig depth*
20.8in
Height to top of cab*133.3
133.2in
Blade width - Standard
105.4in
Blade width - Wide
123.5in
Overall width - 30.5L-32 NOAW
126.6in
Overall width - 30.5L-32 2X Ring
126.6in
Overall width - 30.5L-32
133.3in
Overall width - 35.5L-32 NOAW
139.1in
Overall width - 35.5L-32
145.8in
Weight - Dual Function
47488lb
Wheelbase
160.7in
Ground level to top arch/boom* - Dual Function
177.8in

Lift Chart

Lift height, furthest - Dual Function
86.6in
Sorting Capacity
44.3in
Lift lowest, furthest - Dual Function
14.9in
Ground level to axle center line* - Dual Function
33.2in
Reach highest, retracted - Dual Function
64.0in
Reach lowest, retracted - Dual Function
74.1in
Reach lowest, furthest - Dual Function
112.7in
Reach highest, furthest - Dual Function
118.4in
Lift height, retracted - Dual Function
118.3in

Service Refill

Fuel Tank
99.8gal
Cooling System
15.1gal
Differential, Final Drive - Rear
13.7gal
Engine Oil
7.1gal
Transmission, Torque Converter
14.3gal
DEF Tank
5.0gal
Differential, Final Drive - Tank
17.2gal
Differential, Final Drive - Total
32.5gal
Differential, Final Drive - Front
13.7gal
Parking Brake
14.4oz

Power Train

Travel Speed - Fwd. 1st
3.5mph
Travel Speed - Fwd. 2nd
4.7mph
Travel Speed - Fwd. 3rd
6.5mph
Travel Speed - Fwd. 4th
8.8mph
Travel Speed - Fwd. 5th
11.8mph
Travel Speed - Rev. 1st
3.5mph
Travel Speed - Rev. 2nd
6.5mph
Travel Speed - Rev. 3rd
11.8mph
Travel Speed - Fwd. 6th
12.4mph
Transmission
Countershaft Powershift
Transmission Cooler Type
Water to Oil

Hydraulic System

Type
Load sense, closed center
Pump Type
Variable displacement piston pump
Pump Output
58gal/min

Grapple Dimensions

Grapple capacity
22.0ft2
Tip to tip height
93.19in
Tong opening
143.78in
Full open height
78.66in
Minimum stem diameter
12.01in
Full closed height
62.09in

Winch - Retrival Winch

Type
Hydraulically driven
Max Line Pull - Bare Drum
40016lbf
Max Line Speed
134ft/min
Drum Diameter
9in
Drum Width
10in
Drum Capacity 19.0mm (3/4in)
195ft
Drum Capacity 25.4mm (1in)
85ft

Brakes

Service
Enclosed wet single disc
Transmission Cooler Type
Spring applied, hydraulic released

Winch - Logging Winch

Type
Hydraulically driven
Max Line Pull - Bare Drum
40016lbf
Max Line Speed
280ft/min
Drum Diameter
9in
Drum Width
10in
Drum Diameter
195ft
Drum Capacity 25.4mm (1 in)
85ft

Standard Equipment

  • Electrical
    • 24V electrical system
    • Alarm, back-up
    • Alternator, 115-amp
    • Batteries, maintenance free (2-1000 CCA)
    • Lighting system, halogen (4 total)
    • Main disconnect switch with Diesel Exhaust Fluid (DEF) purge indicator light
    • Starter, electric, heavy duty
    • Starting and charging system
    • Diagnostic connector
  • Operator Environment
    • Cab, enclosed ROPS, FOPS, and OPS certified
    • HVAC system, high performance
    • Seat, High back air suspension with lap seat belt
    • Power port, 12V
    • Converter, 24V to 12V
    • Beverage holder (2)
    • Headliner with dome light
    • Floormat, non permeable and removable
    • Mirror, rear view
    • Computerized Monitoring System
  • Powertrain
    • Engine, Cat C7 With Acert Technology
      • EPA/ARB Tier 4 Final and EU Stage IV Equivalent Engine with Cat Clean Emissions Module (CEM)
    • Fuel priming pump, electric
    • Fuel transfer pump (electric)
    • Fuel filters, inline, primary and secondary
    • Air Precleaner, Turbine
    • Air Cleaner, 2-stage
    • Cooling, Cross-flow System With Stationary Cores And Swing Out Panel
    • Reversing cooling fan, hydraulically driven on demand
    • Transmission, countershaft powershift (6F/3R)
    • Lock-up torque converter
    • Lubed for life driveline slipjoint and universal joints
    • Axles, heavy duty Cat inboard planetary approved for wide tires up to 73-44 with chains
    • Differential locks, independent front and rear
    • Four-wheel enclosed disc service brakes
    • Parking brake, hydraulically released, spring applied
    • Fuel tank, high capacity
  • Hydraulics
    • Load Sense Hydraulics
    • Pumps, variable displacement main and fan
    • Main control valve, high performance and multifuntioning
    • Filter, in-tank return
    • CAT ToughGuard hoses
  • Other Standard Equipment
    • Access panels, hinged or removable
    • Articulation lock link
    • Center Hitch, dual tapered roller bearing upper and lower
    • Ecology drains (engine oil, engine coolant, hyd tank, axles, transmission)
    • Fuel fill, ground level
    • Frames, heavy duty
    • Limb risers, heavy duty
    • Segregated compartments, engine/CEM and cooling
    • Product Link
    • Single side engine service
    • S·O·SSM sampling ports
    • Tilt Cab
    • Vandalism protection, lockable doors and cap locks

Optional Equipment

  • Arch / Boom
    • Cable
    • Single function
    • Dual Function
  • Fenders, heavy duty
  • Winch
    • Retrieval
    • Logging
  • Blade
    • Standard
    • Wide
  • Starting Aids
    • Receptacle, jump start
    • Starting, cold weather
  • Lights, LED working (additional 8 lights)
  • Screens, window & wiper protection
  • Wipers, front and rear
  • Water tank
  • Steering, secondary
  • Tires
    • 30.5L-32 20PR, NOAW *
    • 30.5L-32 26PR , NOAW*
    • 30.5L-32 20PR , 2X Ring**
    • 30.5L-32 26PR , 2X Ring**
    • 30.5L-32 20PR
    • 30.5L-32 26PR
    • 35.5LB-32 20PR, NOAW*
    • 35.5LB-32 24PR, NOAW*
    • 35.5L-32 20PR
    • 35.5L-32 24PR
    • * NOAW – Narrow Overall Width
    • ** 2X Ring – Inner dual tire rim with integrated dual ring mounting of 24.5L-32 outer tire