844 Wheel Dozer

Maximize productivity in mining applications with the Cat® 844 Wheel Dozer, designed with efficiency in mind. Enhanced maintenance capabilities and simplified serviceability make for a long lifecycle, low owning and operating costs, and more uptime. Move more material with a machine built for the toughest conditions.

Key Specs

  • Engine Model Cat® C27
  • Operating Weight 165089 lb
  • Net Power - SAE J1349:2011 - Standard Ambient 732 hp

Benefits

IMPROVED EFFICIENCY

Lock-up torque converter, combined with an on-demand cooling fan and advanced engine idle management, delivers a more smooth shift

ENHANCED MAINTENANCE

Service access is conveniently located, helping to reduce maintenance time

ADDITIONAL SAFETY

Grouped, ground level engine and machine controls allow for safe and easy daily maintenance

Engine

Engine Model Cat® C27
Net Power - SAE J1349:2011 - Standard Ambient 732hp
Rated Speed 1800r/min
Emissions Option 1 - U.S. EPA Tier 4 Final / EU Stage V
Engine Power - ISO 14396:2002 786hp
Gross Power - SAE J1995:2014 801hp
Net Power - SAE J1349:2011 - High Ambient 681hp
Emissions Option 2 - China Nonroad Stage III emissions standards, equivalent to U.S. EPA Tier 2
Engine Power - ISO 14396: 2002 752hp
Gross Power - SAE J1995:2014 766hp
Net Power - SAE J1349:2011 - Standard Ambient 699hp
Net Power - SAE J1349:2011 - High Ambient 648hp
Bore 5.4in
Stroke 6in
Displacement 1649.5in³
Peak Torque - Speed 2624lb/ft
Torque Rise 18%
Note Net power advertised is the power available at the flywheel when the engine is equipped with fan at minimum speed, air intake system, exhaust system, and alternator.

Operating Specifications

Operating Weight 165089lb
Blade Capacity Range 20.8yd³

Transmission

Transmission Type Cat Planetary Power Shift
Converter Drive - Forward 1 4.5mile/h
Converter Drive - Forward 2 8.3mile/h
Converter Drive - Forward 3 14.2mile/h
Converter Drive - Reverse 1 4.9mile/h
Converter Drive - Reverse 2 9.1mile/h
Converter Drive - Reverse 3 15.5mile/h
Direct Drive - Forward 1 Lock-up disabled
Direct Drive - Forward 2 8.5mile/h
Direct Drive - Forward 3 15.2mile/h
Direct Drive - Reverse 1 5.4mile/h
Direct Drive - Reverse 2 9.6mile/h
Direct Drive - Reverse 3 16.4mile/h
Note Travel speeds based on 45/65-45 L-5 46 ply tires.

Hydraulic System - Lift/Tilt

Output at 2,000 rpm and 6900 kPa (1,000 psi) 82gpm
Cylinders, Double Acting - Lift, Bore and Stroke 133 mm × 1535 mm (5.25 in × 60.4 in)
Cylinder, Double Acting - Tilt and Tip, Bore and Stroke 210 mm × 188 mm (8.25 in × 7.4 in)
Relief Valve Setting - Bulldozer (Large Pump) 2700psi
Relief Valve Setting - Tilt Cylinders (Small Pump) 2920psi

Hydraulic System - Steering

Steering System - Circuit Pilot, load sensing
Steering System - Pump Piston, variable displacement
Minimum Turning Radius - Over Blade 34ft
Total Steering Angle 35°
Maximum Flow 94.3gpm
Relief Valve Setting 4500psi

Service Refill Capacities

Fuel Tank - Standard 286.6gal (US)
Cooling System 54.9gal (US)
Crankcase 20gal (US)
Transmission 29.1gal (US)
Differential - Final Drives - Front 71.6gal (US)
Differential - Final Drives - Rear 68.9gal (US)
Hydraulic System - Implement and Hydraulic Fan 68.9gal (US)
Hydraulic System - Steering and Braking 34.9gal (US)

Air Conditioning System

Air Conditioning The air conditioning system on this machine contains the fluorinated greenhouse gas refrigerant R134a or R1234yf. See the label or instruction manual for identification of the gas. - If equipped with R134a (Global Warming Potential = 1430), the system co

Axles

Front Fixed
Rear Trunnion
Oscillation Angle 8.5°

Brakes

Brakes Meets ISO 3540:2011

Sound Performance - Tier 4 Final / Stage V

Operator Sound Pressure Level (ISO 6396:2008) 72dB(A)
Machine Sound Power Level (ISO 6395:2008) 116dB(A)
Operator Sound Pressure Level (ISO 6396:2008)* 72dB(A)
Machine Sound Power Level (ISO 6395:2008)* 114dB(A)
Note (1) *Sound suppression equipped
Note (2) The machine sound power level was measured according to ISO 6395:2008. The measurement was conducted at 70 percent of the maximum engine cooling fan speed.
Note (3) The operator sound pressure level was measured according to ISO 6396:2008. The measurement was conducted at 70 percent of the maximum engine cooling fan speed.
Note (4) Hearing protection may be needed when the machine is operated with a cab that is not properly maintained or when the doors or windows are open for extended periods or in a noisy environment.

Sound Performance - Tier 2

Operator Sound Pressure Level (ISO 6396:2008) 72dB(A)
Machine Sound Power Level (ISO 6395:2008) 116dB(A)
Operator Sound Pressure Level (ISO 6396:2008)* 72dB(A)
Machine Sound Power Level (ISO 6395:2008)* 114dB(A)
Note (1) *Sound suppression equipped
Note (2) The machine sound power level was measured according to ISO 6395:2008. The measurement was conducted at 70 percent of the maximum engine cooling fan speed.
Note (3) The operator sound pressure level was measured according to ISO 6396:2008. The measurement was conducted at 70 percent of the maximum engine cooling fan speed.
Note (4) Hearing protection may be needed when the machine is operated with a cab that is not properly maintained or when the doors or windows are open for extended periods or in a noisy environment.

Cab

ROPS/FOPS ISO 3471:2008 and ISO 3449:2005 Level II Standards

Dimensions (Approximate)

Height - Top of ROPS 17.2ft
Height - Top of Exhaust Pipe 16.6ft
Height - Top of Hood 12.7ft
Ground Clearance 2ft
Centerline of Front Axle to Hitch 7.5ft
Centerline of Rear Axle to Edge of Bumper 12.5ft
Wheel Base 15.1ft
Length - With Blade on Ground 36.5ft

Benefits and Features

  • The full box-section rear frame resists torsional shock and twisting forces.
  • Solid through-width push beams transfer and absorb stresses through a larger portion of the frame.
  • Robust structures withstand the toughest conditions and multiple lifecycles to help improve your bottom line.
  • Resilient, durable blades are designed with excellent dozing and rolling characteristics.
  • Optimized axle mounting helps result in increased structural integrity.
  • Castings in the engine and frame are used in high stress areas to spread high loads.
  • One-piece castings help enhance strength in key pin areas.

Benefits and Features

  • Experience reliable efficiency with complete control over injection timing, duration, and pressure with Mechanically Actuated Electronic Unit Injection (MEUI™).
  • World-class Cat planetary powershift transmission features consistent, smooth shifting and efficiency through integrated electronic controls.
  • Extended engine life and improved fuel efficiency with reduced rated speed.
  • Impeller Clutch Torque Converter (ICTC) and Rimpull Control System (RCS) help provide precise rimpull control.
  • Load sensing hydraulic steering system enables precise machine control for easier loading.
  • Lock-up torque converter with advanced control of lock-up speed.
  • On demand cooling fan helps protect investment and helps lengthen lifecycle.

Benefits and Features

  • Battery disconnect, emergency engine shutdown, and stairway light switch are accessed through the ground level power service center.
  • Optional Cat Detect with Object Detection System (rearview camera and radar) or Vision (rearview camera) help increase operator awareness around the machine.
  • Cab-mounted LED strobes provide warning for others near the machine.
  • Wider stairs with reduced stair angles help increase safety for operators.
  • Access stairs via a powered platform from cab or ground level and have emergency exit access.

Benefits and Features

  • Integrated technologies assist with monitoring, managing, and enhancing your jobsite operations.
  • Product Link™ remote monitoring helps provide valuable insight into machine or fleet performance through the VisionLink® interface, so you can make decisions that boost jobsite efficiency and lower operating costs.
  • Vital Information Management System (VIMS™) touchscreen monitor gives access to a wide range of sensor information and enhanced machine data to resolve problems before machine failure.
  • Optional Cat Detect technologies help enhance awareness of the environment around the machine for increased safety.

Benefits and Features

  • Steering and Transmission Integrated Control System (STIC™) combines directional selection, gear selection, and steering into a single lever, helping to maximize responsiveness and control while reducing operator fatigue.
  • Operators can easily enter and exit the cab with fold-up STIC steer/armrest, reduced access stairway angles, and standard stairway lighting.
  • Experience reduced vibrations with isolated cab mounts and seat-mounted implement and steering controls.
  • Reduced interior sound levels help keep operators comfortable throughout their entire shift.

Benefits and Features

  • Meets U.S. EPA Tier 4 Final emissions standards or equivalent to U.S. EPA Tier 2.
  • Automatic Engine Idle Shutdown helps conserve fuel when machine is not in use.
  • Generate less waste with maintenance-free batteries.
  • Maximize machine life and lower operating costs with Caterpillar Reman and Certified Rebuild programs, which utilize reused or remanufactured components for 40 to 70 percent cost savings.
  • Retrofit packages from Caterpillar deliver new features to older machines to get the most from your investment.

Benefits and Features

  • Swing-out fuel, hydraulic oil coolers, and condenser allow for easy access cleanout.
  • Machine features ground level or platform access to easily reach daily service points.
  • Swing-out doors on either side of the engine compartment help provide easy access to critical daily service checks.
  • Optional tire pressure monitoring system provides real-time information to the operator in the cab for optimized tire life.
  • Electronics bay is conveniently located inside the cab.
  • Sight gauges offer quick visual inspection to help minimize fluid contamination.
  • Lighting inside the engine compartment helps improve visibility to service points.
  • Ecology drains help prevent spills and allow for easier service.
  • 500-hour engine oil and filter change interval with S•O•S oil sampling analysis.
  • Service center includes drain and fill, electronic technician connection, and fluid level status.
  • Axle oil cooler and Automatic Retarder Control helps prevent unnecessary wear from accelerating down declines.

Benefits and Features

  • Dependable blades are designed for mining with press rib construction and optimized widths and capacities for excellent dozing and rolling.
  • Heavy-Duty Semi-U blade includes a Hardox 400 Liner plate, side plates, and additional reinforcements at the bottom of the blade.
  • Equipped with the Cat MineStar System, a suite of integrated mine operations and mobile equipment technologies.
  • Cat MineStar’s capabilities help manage all aspects of operation.
  • Fleet provides remote machine tracking capabilities.
  • Terrain for Loading helps enable high precision management of load management.
  • Detect assists the operator with areas of limited visibility.
  • Health delivers machine condition and operating data and diagnostic tools for a long machine lifecycle.

Standard Equipment

  • Note
    • Standard and optional equipment may vary. Consult your Cat dealer for details.
  • Electrical And Lighting
    • Alternator, 150 amp
    • Batteries, maintenance free (4 - 1,400 CCA)
    • Battery disconnect and jump start receptacle, bumper
    • Deutsch terminal connectors
    • Electrical system, 24V
    • Electronic transmission control
    • Lighting system, halogen (front and rear) lighting, access stairway, engine compartment
    • Starter lockout in bumper
    • Starting and charging system, 24V
    • Transmission lockout in bumper
  • Powertrain
    • Brakes, oil cooled, multi-disc, service/secondary
    • Driveline parking brake
    • Engine Cat C27
    • Fuel priming pump (electric)
    • Ground level engine shutdown switch
    • Precleaner, engine air intake (above hood)
    • Radiator, Aluminum Modular (AMR)
    • Starting aid, (ether) automatic
    • Throttle Lock electronic
    • Torque Converter, Impeller clutch with lock-up clutch (ICTC) and rimpull control system
    • Transmission, 534 mm (21 in) planetary power shift (electronic) (3F/3R)
  • Operator Environment
    • Advisor display, displays real time operating information, performs calibrations and customizes operator setting
    • Air conditioner and heater with automatic temperature control
    • Air precleaner, powered
    • Cab, sound-suppressed pressurized, separate external rolloever protective structure/falling objects protective structure (ROPS/FOPS)
    • Cigar lighter and ashtray
    • Coat hook
    • Converter (12V, 10/15 amp) and power port
    • Electro-hydraulic blade controls (joystick)
    • Heater and defroster
    • Horn, electric
    • Instrumentation, gauges: - engine coolant temperature, fuel level, hydraulic oil temperature, powertrain oil temperature, tachometer
    • Instrumentation, warning indicators: - Action alert system, three category - Automatic transmission model enable status - Brake malfunction - Bucket float status - Delayed engine shutdown status - Engine idle shutdown status - Engine malfunction - Fuel economy mode enable status - Hydraulic lockout - Lockup clutch enable status - Low fuel level - Parking brake status - Rimpull control enable status - Seatbelt warning - Secondary steering (if equipped) - Throttle lock status - Transmission gear
    • Light, dome (cab)
    • Lunchbox and beverage holders
    • Seat, premium with heated and actively cooled leather, adjustable lumbar support, air adjustable bolsters on the seat and backrest, seat cushion tilt adjustment, and adjustable-length seat cushion
    • Radio, AM/FM with Bluetooth®, USB Port, 3.5 mm AUX input
    • Tinted glass
    • Wet-arm wipers/washers (front, rear and corner) intermittent front wiper
  • Safety
    • Alarm, back-up
    • Camera, rear vision
    • Emergency platform exit
    • Implement lockout switch
    • Mirrors, rearview (externally mounted)
    • Seat belt, retractable, 76 mm (3 in) wide
    • Stairway, left and right rear access
    • Steering and transmission lock lever, cab
    • Steering, secondary
    • Seat, trainer with lap belt, 76 mm (3in) wide
    • Toe kicks
  • Service
    • Axle ecology drains
    • Case drain filters
    • Coupling, Caterpillar O-ring face seals
    • Engine, crankcase, 500 hour interval with CH4
    • Front walkway around cab
    • Guards, crankcase and powertrain
    • Grouped/labeled lube points
    • Battery disconnect and jump start receptacle, bumper
    • Hitch, drawbar with pin
    • Hoses, Cat XT
    • Oil sampling valves
    • Sight guages for steering, implement and transmission oil
    • Vital Information Management System (VIMS) 3G with graphical information display: external data port, customizable operator profiles
  • Cooling
    • Standard ambient package (recommended for site conditions that do not exceed 43°C (110°F)
  • Cold Weather
    • Heated seat
  • Efficiency
    • Economy mode with on demand throttle
    • Positive flow control hydraulic system
    • Impeller Clutch Torque Converter (ICTC) with lock-up clutch
    • Steering, load sensing
    • Soft detent controls
    • Engine idle management features: - Auto idle kickdown - Delayed engine shutdown - Engine idle shutdown
  • Tramming
    • Front fenders

Optional Equipment

  • Note
    • Standard and optional equipment may vary. Consult your Cat dealer for details.
  • Electrical And Lighting
    • Lights, LED
    • Product Link (Cellular)
    • Product Link (Satellite)
  • Powertrain
    • Engine brake
    • No-spin rear axle
    • No-spin rear axle and oil cooler
    • Precleaner, raised
  • Operator Environment
    • Radio, Sirius XM/AM/FM radio with Bluetooth technology, USB port, 3.5 mm AUX input
    • Rubber mounted cab glass
    • Window sun screen
  • Safety
    • LED warning strobe
  • Service
    • Product Link
  • Blades
    • HD Semi-U - 16.1 m3 (21.1 yd3)
    • Paint, black blade rear
  • Cooling
    • High ambient cooling - software (recommended for site conditions that do not exceed 49°C [121°F]
  • Cold Weather
    • 50° C (-58° F) antifreeze
    • 120V or 240V coolant heating elements (recommended in conditions from -18°C to -30°C [0°F to -22°F]
    • -40°C (-40°F) Hydraulic Oil, Arctic
  • Tramming
    • Fender extensions, roading, front and rear