321D LCR

Increased work tool options, new powerful engine and easier operation lead to increased productivity and lower operating costs.

Engine Model Cat® C6.4 ACERT™
Net Flywheel Power 148.0 hp
Net Power - ISO 9249 148.0 hp
Bore 4.02 in
Stroke 5.12 in
Displacement 389.0 in3
Net Power - EEC 80/1269 148.0 hp
Net Power - SAE J1349 148.0 hp

Operating Weight 51875.0 lb
Operating Weight - Std. Undercarriage 51875.0 lb
Operating Weight - Long Undercarriage 51875.0 lb
Operating Weight - Long Undercarriage 2 53308.0 lb

Maximum Drawbar Pull 46311.0 lb
Maximum Travel Speed 3.5 mph

Hydraulic System
Main Implement System - Maximum Flow (2x) 54.0 gal/min
Max. Pressure - Equipment 5076.0 psi
Max. pressure - Heavy Lift 5221.0 psi
Max. Pressure - Travel 5076.0 psi
Max. Pressure - Swing 3626.0 psi
Pilot System - Maximum Flow 9.0 gal/min
Pilot System - Maximum Pressure 566.0 psi
Boom Cylinder - Bore 4.7 in
Boom Cylinder - Stroke 49.6 in
Reach Stick Cylinder - Bore 5.5 in
B1 Family Bucket Cylinder - Bore 4.7 in
Reach Stick Cylinder - Stroke 59.8 in
B1 Family Bucket Cylinder - Stroke 43.5 in

Service Refill Capacities
Fuel Tank Capacity 87.0 gal
Cooling System 6.6 gal
Engine Oil 8.0 gal
Swing Drive 2.1 gal
Final Drive (each) 2.1 gal
Hydraulic System (including tank) 55.0 gal
Hydraulic Tank 32.0 gal
Hydraulic Tank (Including suction pipe) 35.0 gal

Sound Performance
Performance ANSI/SAE J1166 APR 90

Brakes SAE J1026 APR90
Cab/FOGS SAE J1356 FEB88

Swing Mechanism
Swing Speed 11.5 RPM
Swing Torque 45612.0 lb ft

Number of Shoes (each side) - Long Undercarriage 49
Number of Track Rollers (each side) - Long Undercarriage 8
Number of Carrier Rollers (each side) - Long Undercarriage 2

Transport width 125.2 in
Shipping Height 9.9 ft

Compact Radius
The 321D LCR delivers outstanding performance and comfort.

Compact Radius

Compact Radius
The 321D LCR features a compact radius design, which makes it ideal for working in space restricted areas such as: close to buildings, road construction - limiting lane closures or logging roads. The tail swing is just 1.68 m (5’6”) as compared to the 2.75 m (9’0”) on the 320D. When rotated 90 degrees and working over the side, a minimal amount of counterweight extends beyond the track width.

Operator Confidence
Due to the 321D LCR’s compact working envelope, operators can work confidently knowing that the counterweight will not swing into any object behind them.

The cab on the 321D LCR is a comfortable place to work, with low sound levels, good visibility and convenient access to switches and controls. The 321D LCR cab offers many of the same amenities and options found in the cab of the 320D/320D LRR.

Working Envelope
To further minimize the working envelope, the boom is repositioning more towards the center of the machine as compared to a standard excavator. This reduced the front swing radius when the boom is pulled all the way up and the stick brought in completely. This design also increases the lift capacity of the 321D LCR over the front as it has a better mechanical advantage when compared to a standard excavator.

C6.4 with ACERT™ Technology
The Cat® C6.4 gives the 321D LCR exceptional power and fuel efficiency unmatched in the industry for consistently high performance in all applications.

C6.4 with ACERT™ Technology

Cat C6.4
The Cat C6.4 with ACERT™ Technology introduces a series of evolutionary, incremental improvements that provide breakthrough engine technology. The building blocks of ACERT Technology are fuel delivery, air management and electronic control. ACERT Technology optimizes engine performance while meeting U.S. EPA Tier 3 emission regulations. With its proven technology, robust components and precision manufacturing, you can count on this engine to power up at start time and keep working productively all shift long.

ADEM™ A4 Engine Controller
The ADEM A4 electronic control module manages fuel delivery to get the best performance per liter of fuel used. The engine management system provides flexible fuel mapping, allowing the engine to respond quickly to varying application needs. It tracks engine and machine conditions while keeping the engine operating at peak efficiency.

Fuel Delivery
The Cat C6.4 features electronic controls that govern the fuel injection system. Multiple injection fuel delivery involves a high degree of precision. Precisely shaping the combustion cycle lowers combustion chamber temperatures, generating fewer emissions and optimizing fuel combustion. This translates into more work output for your fuel cost.

Cat® hydraulics deliver power and precise control to keep material moving.


Component Layout
To optimize efficiency of hydraulic performance, the hydraulic components are located close together, which reduces friction loss and pressure drops in the lines.

System Pressure
System pressure has been increased to 35 000 kPa (5076 psi), which attributes to improved performance:
  • Increased stick and bucket forces (up 7% higher than the 321C LCR) to better handle those tight digging conditions
  • More drawbar pull (206 kN - 46,322 lb) to provide more ability to climb slopes, easier spot turns and improved travel in poor underfoot conditions
  • More lift capacity, generally over the front where you are generally hydraulically limited

Heavy Lift
The 321D LCR features the addition of a heavy lift, which increases system pressure to 36 000 kPa (5220 psi), giving even more lift capacity over the front. Heavy Lift is activated be depressing the soft switch on the right hand conslole. As the pressure increases, the engine speed is reduced, which allows better control while lifting objects.

Pilot System
The pilot pump is independent from the main pumps and controls the front linkage, swing and travel operations.

Hydraulic Cross Sensing System
The hydraulic cross sensing system utilizes each of two hydraulic pumps to 100 percent of engine power, under all operating conditions. This improves productivity with faster implement speeds and quicker, stronger pivot turns.

Boom and Stick Regeneration Circuit
Boom and stick regeneration circuit saves energy during boom-down and stick-in operation which increases efficiency, reduces cycle times and pressure loss for higher productivity, lower operating costs and increased fuel efficiency.

Auxiliary Hydraulic Valve
The auxiliary valve is standard on the 321D LCR. Control Circuits are available as attachments, allowing for operation of high and medium pressure tools such as shears, grapples, hammers, pulverizers, multi-processors and vibratory plate compactors.

Hydraulic Cylinder Snubbers
Snubbers are located at the rod-end of the boom cylinders and both ends of the stick cylinders to cushion shocks while reducing sound levels and extending component life.

The monitor is a full color Liquid Crystal Display that gives you vital operating and performance information, alerts in text, all in a simple, east to navigate format.

Operator Comfort
Caterpillar offers the most intuitive and easy to operate excavators while providing great all around visibility and exceptional operator comfort.

Operator Comfort

Operator Station
The layout of the interior has been redesigned to maximize operator comfort and reduce operator fatigue.
  • Frequently used switches have been relocated for easier access.
  • Consoles and armrests have been redesigned for better comfort and adjustability.
  • More seat options - choose from the standard mechanical suspension seat, or the optional air suspension seat with heater. Both provide excellent comfort.

Standard Cab Equipment
To enhance operator comfort and productivity, the cab includes a lighter, drink holder, coat hook, service meter, literature holder, magazine rack and storage compartment.

Joystick Control
Joystick controls have low lever effort and are designed to match the operator’s natural wrist and arm position.

Hydraulic Activation Control Lever
For added safety, this lever must be in the operate position to activate the machine control functions.

Climate Control
Climate control adjusts temperature and flow, and determines which air outlet is best in each situation with a touch of a button.

321D LCR is designed to handle the most rugged operating conditions, while providing long life and value.


Robust Undercarriage
A solid foundation built tough to absorb the stresses of everyday work.
  • Rollers and idlers are sealed and lubricated to extend service life.
  • track links are assembled and sealed with grease to decrease internal bushing wear and increase life by as much as 25%, when compared to dry seal undercarriages.
  • Spring recoil system stroke has been increased to better relieve excess track tension, which can occur when material builds up between the track and sprocket.

Booms, Sticks and Bucket Linkages
Built for Performance and long service life, Caterpillar® booms and sticks are large, welded, box-section structures with thick, multi-plate fabrications in high stress areas.

Booms, Sticks and Bucket Linkages

Front Linkage Options
The Reach Boom allows excellent all-around versatility and a large working envelope. It can be equipped with the following two sticks:
  • R2.9B1 - performs well in a mid-range working envelope
  • R2.5B1 - a good match when the job requires a larger bucket or a hammer

Work Tools - Attachments
The 321D LCR has an extensive selection of work tools to optimize machine performance.

Work Tools - Attachments

Wide Variety of Work Tools
Caterpillar offers a complete line of work tools to match all of your application needs:
  • Hammers - matched to Cat machines for optimum performance
  • Thumbs, Stiff Link, Full Rotation - transforms your 321D LCR into a versatile material handling machine
  • Grapples - choose from a large variety of grapples that best suit your application
  • Multi-processors - does the work of many types of demolition tools by use of interchangeable jaws
  • Shears - features 360 degree rotation and high force to weight ratio
  • Pulverizers - ideally suited for rapid, non-explosive demolition applications
  • Vibratory Plate Compactors - provide superior compaction force in a reliable, low maintenance package
  • Rippers - perfectly suited for trenching and pipeline applications where conditions aren't favorable to traditional ripping methods

Caterpillar Buckets
The most extensive choice of buckets that can optimize machine performance and match your application needs.
  • General Purpose Buckets - for digging in low impact, moderately abrasive materials such as dirt, loam, gravel and clay.
  • Heavy-Duty Buckets - for use in abrasive applications such as mixed dirt, clay and rock.
  • Heavy-Duty power Buckets - for use in abrasive applications where breakout force and cycle times are critical - good for materials such as mixed dirt, clay and rock.
  • Ditch Cleaning Buckets - wide and shallow for ditch cleaning, bank forming and finishing.

Caterpillar Ground Engaging Tools (GET)
Choose from a wide variety of tips that maximize bucket and machine performance. Sidecutters and sidebar protectors are also available.

Multiply the versatility and utility of 321D LCR.
  • Hydraulic Pin Grabber Plus - allows quick and easy tool changes without having to leave the cab. Picks up a large variety of tools equipped with standard pins.
  • Dedicated Coupler - no loss of tip radius, maximizing the breakout forces on your 321D LCR.

Product Link
Both the PL121 and PL321 are available as factory installed attachments.PL121 gives you Asset Watch, which includes the following features:
  • Engine hours
  • Machine location
  • Time based fences (when the machines can operate)
  • Geo-based fences (boundaries that the machine can operate)PL321 gives you all of the features listed for PL121, plus the ability to include Health and Maintenance Watch.
  • Health Watch ° Codes from on-board EDM's/Sensors ° Estimated Fuel Consumption ° Fuel Watch
  • Maintenance Watch
° Preventative Maintenance Planning ° Preventative Maintenance Checklists ° Overdue PM Notification ° PM History Recording

Machine Security
An optional Machine Security System is available from the factory on the 321D LCR. This system controls when the machine can be operated and utilizes specific keys to prevent unauthorized machine use, a significant theft deterrent.

More Attachments
The 321D LCR offers the most options available to equip your machine to best match your application and work environment requirements. From track shoe size to guarding packages to operator comfort options, the 321D LCR offers more options.

Pump Compartment
A service door on the right side allows for ground level access to the hydraulic pump, case drain and pilot filters.

Greasing Points
A concentrated remote greasing block on the boom delivers grease to hard-to-reach locations on the front.

Anti-Skid Plate
Anti-skid plate covers top of storage box and upper structure to prevent slipping during maintenance.

Diagnostics and Monitoring
The 321D LCR is equipped with S•O•SSM sampling ports and hydraulic test ports for the hydraulic system, engine oil, and for coolant. A test connection for the Cat Electronic Technician (Cat ET) service tool is located in the cab.

A wide variety of optional factory-installed attachments are available to enhance performance and improve job site management.


Auxiliary Hydraulic Options
Allows you to configure your 321D LCR to meet your work tools needs, while increasing its versatility.
  • Single Function Circuit - suited for tools that require one-way flow with both pumps, such as hammers, vibratory plate compactors.
  • Double Function Circuit - suited for tools that require two-way flow, utilizing one pump, such as thumbs or non-rotation grapples or shears.
  • Tool Control System
- accommodates single or double function tools, as well as rotating tools when equipped with medium pressure. - Stores pressure and flow information for up to 10 tools - Cat tools selectable that have preset flows and pressures - Shortcut button on right hand console, making tool selection easier.

Service and Maintenance
Simplified service and maintenance features save you time and money.

Service and Maintenance

Ground Level Service
The design and layout of the 321D LCR was made with the service technician in mind. Many service locations are easily accessible at ground level allowing critical maintenance to get done quickly and efficiently.

Air Filter/Radiator Compartment
The left rear service door allows easy access to the engine radiator, oil cooler and air-to-air-aftercooler. A wire mesh screen is provided between the aftercooler and radiator/oil cooler, where these is enough clearance to blow off debris using a wand. The air filter, also located within this compartment, features a double-element construction for superior cleaning efficiency. When the air cleaner plugs, a warning is displayed on the monitor screen inside the cab. Access to the washer tank and maintenance points for the electric components, such as the battery, circuit breaker and controller are also located in this compartment. the jump-start receptacle, which is an attachment for the cold weather package, is located near the battery.

Complete Customer Support
Cat® dealer services help you operate longer with lower costs.

Complete Customer Support

Product Support
You will find nearly all parts at our dealer parts counter. Cat dealers utilize a worldwide computer network to find in-stock parts to minimize machine down time. Save money with remanufactured components.

Machine Selection
Make detailed comparisons of the machines you are considering before you buy. What are the job requirements, machine attachments and operating hours? What production is needed? Your Cat dealer can provide recommendations.

Customer Support Agreements
Cat dealers offer a variety of product support agreements, and work with customers to develop a plan the best meets specific needs. These plans can cover the entire machine, including attachments, to help protect the customer’s investment.

Improving operating techniques can boost your profits. Your Cat dealer has videotapes, literature and other ideas to help you increase productivity, and Caterpillar offers certified operator training classes to help maximize the return on your investment.

Maintenance Services
Repair option programs guarantee the cost of repairs up front. Diagnostic programs such as Scheduled Oil Sampling, Coolant Sampling and Technical Analysis help you avoid unscheduled repairs.

Repair, rebuild, or replace? Your Cat dealer can help you evaluate the cost involved so you can make the right choice.

Standard Equipment

  • 50 Ampere alternator
  • Base machine light (frame)
  • Horn
  • Pre-start monitoring system - checks for low fluids
Operator Environment (Mandatory Attachment)
  • Air conditioner, heater, defroster with automatic climate control
  • AM/FM Radio with antenna and 2 speakers
  • Ashtray with 24 volt lighter
  • Beverage/cup holder
  • Bolt-on Falling object Guarding System (FOGS) capability
  • Cab Glass Openable and retractable two- piece front windshield Sky-light, pop-up, polycarbonate
  • Coat hook
  • Floor mat
  • Instrument panel and gauges
  • Joysticks, console mounted, pilot operated
  • Light, interior
  • Literature compartment
  • Monitor, full graphic color display
  • Neutral lever (lock out) for all controls
  • Polycarbonate side windows
  • Positive filtered ventilation
  • Pressurized cab
  • Seat, suspension, with high back and head rest
  • Seat belt, retractable - 76 mm (3 in)
  • Storage compartment suitable for lunch box cooler
  • Sun shade (for skylight)
  • Travel control pedals with removable hand levers
  • Windows, Polycarbonate (mandatory attachment)
  • Windshield wiper and washer (upper and lower)
Engine/Power Train
  • C6.4 with ACERT™ Technology
  • Automatic engine speed control with one touch low idle
  • Cooling
  • Priming pump
  • Straight line travel
  • Two-speed auto-shift travel
  • Water separator in fuel line
  • Grease lubricated track
  • Hydraulic track adjusters
  • Idler and center section track guards
  • Long undercarriage
Other Standard Equipment
  • Automatic swing parking brake
  • Auxiliary hydraulic valve
  • Capability of stackable valves (max of 3) for main valve
  • Capability of auxiliary circuit
  • Counterweight with lifting eyes
  • Door locks, cap locks and Caterpillar® one key security system
  • Fine swing control
  • Fully pressurized hydraulic system
  • Heavy lift
  • Mirrors (frame-right, cab left)
  • S•O•SSM quick sampling valves for engine and hydraulic oil
  • Wave fin radiator
  • Wiring provision for Product Link

Optional Equipment

Front Linkage
  • Booms
  • Sticks
  • Bucket Linkage
  • Boom Lowering Control Device
  • Light, Boom - Right side
  • Lights, Cab mounted (2)
  • Machine Security System (MSS)
  • Power supply (12V-5 AMP)
  • Product Link (PL121SR/PL321SR
  • Travel Alarm (Mandatory attachment)
  • Falling Object Guarding System (FOGS)
  • Front windshield guard
  • Heavy-duty bottom guards
  • Track guiding guards
  • Vandalism guards
Operator Environment
  • Hand control pattern changer (ISO-SAE)
  • Rear window, secondary exit
  • Seat, high back with air suspension and heater
Engine/Power Train
  • Starting, Cold weather package
  • Water level indicator (Fuel)
  • Track shoes
  • Heavy-duty rollers
Auxiliary Hydraulics
  • Hammer Circuit
  • Hydraulic pin grabber quick coupler and controller
  • Lines for booms and sticks
  • Thumb Circuit
  • Tool Control System
Work Tools
  • Wide offering of buckets, tips and sidecutters



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