®®

EngineEngine Model Cat® C27 ACERT™Gross Power 512 kW 687 hpNet Power 468 kW 627 hp

Operating SpecificationsBlade Capacities 15.9-30.7 m3 20.7-40.2 yd3

WeightsOperating Weight 70 815 kg 156,120 lb

844HWheel Dozer

2

844H Wheel DozerA strong power train combined with a heavy-duty front frame provides long lifeand economical operation.

Engineered for demanding work in large dozingapplications, the Cat 844H Wheel Dozer isan ideal match for power generating utilities,clean up, road maintenance and productiondozing at mines.

Complete Customer Support

The Caterpillar® dealer networkprovides world class customer supportand offers a wide range of services thathelp you operate longer with lowercosts. pg. 13

Serviceability

Large engine doors, rear access stairsand convenient service platform withlarge doors enhance serviceability onthe 844H. Hydraulic, transmission andradiator sight gauges make daily checksquick and easy. pg. 12

✔

Structures

The 844H features a box-sectionrear frame and four-plate front frameproviding strength and stability.Together they provide resistanceto dozing shocks and stresses whileabsorbing shock loads and twistingforces. pg. 7

Cooling System

The Next Generation Modular Radiatorwith Air-to-Air Aftercooling Systemhas been added to the 844H to helpmeet emissions requirements andimprove efficiency, serviceabilityand sound levels. pg. 6

✔

Power Train

The Cat® C27 ACERT™ engine is U.S.EPA Tier 3/EU Stage IIIa compliant andcombined with MEUI, ADEM™ IV,axle-shaft brakes and impeller clutchtorque converter with lock-up clutchprovides smooth consistent shiftingwith rimpull control and direct driveefficiency. pg. 4

✔

✔ New Feature

3

Operator Station

Experience high level efficiency,productivity and comfort with the state-of-the-art cab featuring one-hand STIC™operation, excellent ventilation, lowsound levels, large viewing area and anew blade control and trainer’s seat.pg. 10

✔

Blades and Blade Controls

Choose between semi-U, heavy-dutysemi-U and coal blades. Replaceablebolt-on cutting edges and bottom wearplates help extend blade life. A newergonomic, pilot controlled joystick isused to hydraulically control all bladeoperations. pg. 9

✔

Hydraulics

Two, independent hydraulic systemsand load-sensing steering are theinvisible force behind the mobilityand versatility of the 844H. pg. 8

Cat C27 Engine with ACERTTM Technology.Is rated at 468 kW (627 hp) at 2,000 rpm.The MEUI fuel system and ElectronicControl Module (ECM) deliver powerand efficiency in the most demandingapplications. Electronic control providesmany benefits:

• ADEM™ IV

• Automatic altitude deration

• Elevated low idle

• Cold weather starting mode

• Acceleration delay on startup toreduce engine wear

• Advanced diagnostic capabilities

• Automatic control of ether aid

• 500 hour oil change interval withCH-4 oil and new larger oil pan

• Dry-type air cleaner with primaryand secondary elements

• Engine/torque divider module isisolation mounted to the main frameto reduce machine vibration andstructure radiated noise

• Monotherm pistons

Starting System. Is direct-electric24-volt with a 95-amp alternator andtwo 12-volt, 1,300 CCA, 190-amp-hourbatteries.

1 Aftercooler. Lowers inlet chargetemperature. Reduces thermal stressesthat can cause premature wear ofpistons, rings and liners.

2 High Injection Pressures. Independentof engine speed, decrease smoke andemissions while improving response.

3 Oil-Cooled Pistons and Full-Length,Water-Cooled Cylinder Liners. Providemaximum heat transfer for longercomponent life.

4 Engine Oil Cooler. Maintains optimumoil temperature for proper cooling andpressure lubrication. Engine coolingprovided is by the NGMR. Hydrostaticfan drive gives the standard coolingpackage 110° F ambient capability.

Impeller Clutch Torque Converter(ICTC). Allows the operator to modulaterimpull from 100 percent to 20 percentof maximum rimpull. After 20 percentof maximum rimpull is achieved, furtherpedal travel applies the brake. The torqueconverter is equipped with a lockupclutch for direct drive efficiency.

ICTC Benefits.

• Left pedal modulation

• Compensates for wear and providesthe ability to recalibrate for optimumleft pedal modulation regardless oftorque converter wear.

5 Impeller Clutch. Modulates theamount of engine power sent tothe wheels.

6 Lockup Clutch. With Electronic ClutchPressure Control provides direct driveefficiency in second and third forwardgears and all three gears in reversewith higher speeds and improved fueleconomy on long distance dozing.

4

The 844H power train components deliver dependable, reliable performance customersexpect from Cat Wheel Dozers.

Power Train

Planetary, Electronic, Power ShiftTransmission. Is the same transmissionfound in the Cat 990H Wheel Loader.Electronic shifting provides smoothconsistent shifts with fingertip controlshoused in the STIC™ controller.The transmission is built around acenter shaft with a gear set clusterstacked end-to-end to distribute load,conserve space and transfer energyefficiently. Large diameter perimeterclutches coupled with high contactplanetary gear sets provide hightorque carrying capacity for long,trouble-free life.

Parking Brake. Is spring-applied, oil-released and dry disc. It is mountedon the transmission gear output shaft.The Electronic Monitoring System IIIalerts the operator if the transmissionis engaged while the parking brake isapplied as well as if pressure drops, inwhich case the brake will automaticallyapply. Manual override is possible toallow movement of the machine.

• Self-diagnostics accessible throughCaterpillar Monitoring System

• Quick Shift

7 Final Drives. Are planetary consistingof a ring gear, three planet gears, aplanet gear carrier and a sun gear.

• Ring gears splined to reaction hub

• Proprietary gear cutting and heattreat methods are used in themanufacturing of components

• Full-floating bronze sleeve bearingsare used on planet gears

• Oil-bath lubrication

8 Axle-Shaft, Oil-Disc Brakes. Are fullyhydraulic, completely sealed and neverneed adjustment. Disc face groovesprovide cooling even when brakes areapplied for a long, fade resistant life.

Design. Provides a larger cooling oilreservoir and thicker separator platesthan conventional brake designs.This gives the brakes higher heatdissipation rates allowing highercapacity than conventional oil-discbrakes. Duo-cone® seals are locatedbetween the wheel and the spindle.

9 Brake Location. Reduces service time.Conventional brakes require final drivedisassembly. The axle-shaft brake designallows brake service while leaving thefinal drive intact. Reduced service timeand machine downtime keeps operatingcosts low.

Bevel Gear Sets and Differentials.Are common with the Cat 990HWheel Loader.

Service Brakes. Are four wheel, hydraulic,oil-dipped multiple disc brakes that areadjustment-free, completely enclosedand allow modulated engagementwithout slack adjusters.

Secondary Brakes. Are fully modulatedand the front and rear service brakecircuits are isolated so one circuit canoperate if pressure drops in the othercircuit.

5

Next Generation Modular Radiator(NGMR). In order to meet U.S. EPATier 3 and EU Stage IIIa emissionsrequirements. The cooling system hasbeen upgraded to a NGMR that utilizesthe ATAAC system to achieve lowerparticulate, NOx and sound output.The proven NGMR system is currentlyused on other Cat models such as the834H and 988H.

NGMR is a Cat technology thatimproves serviceability and increasescooling efficiency by 22 percent. Ambientworking temperature for the standard844H is 43° Celsius (110° Fahrenheit).A high ambient cooling package with a50° Celsius (122° Fahrenheit) capacityis available as an attachment.

ATAAC System. Provides a separatecooling system for the intake manifoldair complementing the engine jacketwater cooling system. The ATAACsystem routes hot, compressed air fromthe turbo and cools it with a single pass,air-to-air aluminum heat exchanger.The cooled compressed air is thendelivered to the engine intake manifold.Providing the engine with coolcompressed air greatly reduces theemissions produced, meeting Tier 3requirements for a cleaner environment.

Separated Cooling System. Isolatesthe NGMR and demand fan from theengine compartment with a shield,allowing the radiator to receive outsideambient air through the side and topvents at a much lower temperature thanthe hot air from the engine compartment.This improves the system’s efficiencyand allows the radiator size to bedecreased and the rear hood to besloped, improving the rear viewingarea. Also, sound levels are reduceddue to the lower fan speed of a moreefficient cooling system.

Serviceability. Is a key benefit.Tubes are welded to a large, thickheader, providing the strength of thetube-to-header joint that reduces thepossibility of coolant leaks. The NGMRcore design allows removal of a singlecore without removing the entire radiator– reducing downtime through ease ofserviceability. Replacing the individualcore also reduces repair costs.

Two-Pass System. Offers increasedcooling capacity. Coolant travels fromthe engine to the fan side of the bottomtank, up the fan side of each core, overthe top, down the engine side of the core,into the engine side of the bottom tankand back to the engine. The improvedflow pattern allows the coolant to passthrough the radiator twice for bettercooling. The NGMR design improvesserviceability, reduces downtime andincreases cooling capability.

6

Cooling SystemWorks with the engine to meet emissions standards as well as improve serviceabilityand reduce downtime.

Structure Welds. Are more than90 percent robotically welded.This provides highly consistent weldswith deep plate penetration and excellentplate fusion. The benefit is greaterfatigue strength and longer life thanwith conventional welding methods.

Castings. Are used in critical high-stressareas of the engine end frame to helpspread the load and reduce the numberof parts. The casting for the rear trunnionmount also serves as an engine mount,which provides a load path for the weightand torque of the engine to travel downto the trunnion and then on through tothe axle. Other castings used in theengine-end frame include: front trunnionmounts, steering cylinder brackets,articulation stops and lock link.

1 Box-Section Rear Frame. Absorbsshock loads and torsional forces, solidlymaintaining alignment for hitch pinsand driveline.

2 Four-Plate Front Frame. Providesmaximum structural strength to resisttwisting loads during dozing applications.

3 Upper and Lower Hitch Pins. Pivot ondouble-tapered roller bearings and areshaped to direct stress away from theend of the weld, resulting in a smoothertransition of stress loads.

4 Spread-Hitch Design. Helps square upthe frame and provides more clearancefor hydraulic lines. Double taperedroller bearings and hardened pins resistboth horizontal and vertical loads toincrease life. The spread hitch alsomakes service access easier.

Engine and Transmission Mounts.Are designed to use mushroom andcup-shaped ISO mounts, reducingcomponent vibration and sound levels.The engine mounts directly to therear cross member, simplifying andimproving load transfer structure.

7

StructuresAdvanced design, materials and processes provide superior strength.

1 Two Separate Hydraulic Systems.One for lift/tilt/tip and brakes, and theother for steering and the hydraulically-driven engine cooling fan. Benefits oftwo systems are increased cooling andelimination of cross-contamination.If one system runs hot or is contaminated,the other will be unaffected.

2 Blade Control. Low effort, pilot joystickcontrols with integrated lift/tilt/tip arefloor-mounted.

• Caterpillar® built tandem vanepumps provide hydraulic flow forthe lift, tilt and tip functions. Thecircuit is well balanced to providecontrol when all functions are usedsimultaneously.

• Well-proven pumps, valves andcylinders are common with those usedon Cat Large Track-Type Tractors.

• For improved serviceability, allhydraulic pumps are mounted ona single pump drive.

3 Load Sensing Steering with STIC™Control System. Is a revolutionarysystem that integrates steering andtransmission into a single controller.The variable displacement pumpmaximizes machine performance bydirecting power through the steeringsystem only when needed. More efficientuse of power results in decreased fuelconsumption and higher production.

• Simple side-to-side motions of thestick turn the machine right or leftoffering a 35 degree steering anglein both directions. Center-pointframe articulation allows the frontand rear wheels to track.

• Transmission shifting forward,neutral or reverse is controlledby the operator’s fingers and gearselection is controlled by theoperator’s thumb.

XT™-3 and XT™-5 Hose. O-ring faceseals and large-bore lift and tilt cylinderstop off the hydraulic system, deliveringthe performance and durability ownersexpect. Reliable components reduceleaks and help protect the environment.

Hydrostatic Demand Fan. Is used forengine, transmission and hydrauliccooling. A variable displacement pumpdrives the fan’s hydraulic motor sothat fan speed varies with coolanttemperature. The fan draws only thepower needed for cooling, reducing fuelconsumption and increasing efficiency.

8

HydraulicsWell-balanced hydraulics deliver precise, low-effort control and trouble-free operation.

Cat Blades. Are designed with excellentdozing and rolling characteristics.

• Capacities and widths are set toachieve increased productivity

• Special design allows for spreadingof cover material as well as dozingof heavier loads

• High-strength, pressed ribconstruction

• Cat Large Track-Type Tractorbolt-on cutting edges and bottomwear plates

• Fitted with Cat standard hardwareand Ground Engaging Tools (GET)

• Rebuildable for long blade life

Coal Blade. Is designed for precise andproductive dozing while helping to retainload control with increased capacity forlighter materials. Wing angles helpretain the load while dozing.

Semi-U Blade. Combines thecharacteristics of the S and U bladesinto one package. Provides increasedcapacity with the addition of shortwings which include only the dozerend bits without sacrificing spreadingcharacteristics of straight blades.

Heavy-Duty Semi-U Blade. Has thesame configuration as the Semi-U bladebut is built with thicker plates for moresevere applications.

Coal Scoop. Is available throughCat Work Tools.

Heavy-Duty Blade Linkage. Is commonwith a Cat D9 Track-Type Tractor.These well-proven components aredesigned for tough applications.

• Lift cylinders raise and lower bladefor efficient dozing action

• Two position tilt cylinder mountingfor increased flexibility for variousapplications

• Cutting edges are DH-2™ steel

• End bits are DH-3™ steel to providemaximum life

• Trunnions, pusharms and tag linkare sized for large dozing loads

Low Effort, Pilot Operated, JoystickBlade Control. Hydraulically operatesblade raise, lower, tilt and tip.

Lift Circuit. Features four positions:raise, hold, lower and float with detentehold on float.

Tilt/Tip Circuit. Offers operator selectedsingle or dual-tilt and fingertip controlfor easy operation.

9

Blades and Blade ControlsCat blades are built to handle tough applications and well-proven Cat components deliverdependable service and ease of operation.

10

Comfort and control — a top quality operator station helps maximize productivity.

Operator Station

1

2

3

6

5

4

Cab Design. Is spacious and incorporatesinnovations for operator comfort andproductivity, including an excellentviewing area, interior sound levels below75 dB(A), Cat Comfort Series seat,standard coat hook, cup holder, storagebin, sun visor, trainer’s seat with lapbeltand intermittent wet-arm wipers. It isalso radio-ready for two-way radios.

1 STIC™ Control System (SteeringTransmission Integrated Controller).Is a revolutionary system that integratessteering and transmission into a singlecontroller. Simple side-to-side motionsof the operator’s left arm turn the machineright or left. Transmission shifting forward,neutral or reverse is controlled by theoperator’s fingers, and gear selection is controlled by the operator’s thumb.These factors combine to produce a fluidmotion that reduces effort and allows theoperator to work the machine for longperiods of time with little or no fatigue.

2 Left Pedal. Operates the ImpellerClutch Torque Converter for aboutthe first inch of travel, then engages thebrakes. Within the first inch of pedaltravel, rimpull can be controlled from100 percent to 20 percent.

• By turning the Rimpull Control dialto the selected rimpull setting, theamount of power to the ground isadjusted to prevent costly tire slip.

3 Comfort Series Seat. With air suspensionand retractable seat belt is designed forcomfort and support. Seat cushionsreduce pressure on the lower back andthighs while allowing unrestricted armand leg movement. The seat has threeheight levels. The retractable seat beltremains off the floor and is easy forthe operator to reach.

4 Trainer’s Seat. Allows for the trainer/rider to have a seat with lap belt.

Quick-Shift Feature. Allows quickercycle times by shifting from first forwardto second reverse.

Throttle Lock. Allows the operator topreset the engine speed and concentrateon productivity. The throttle lock can bedeactivated by pressing the brake pedal.

5 Electronic Monitoring System III.Continually monitors various machinesystems through three instrument clustersand provides a three-level warningsystem to alert the operator of immediateor pending problems. EMS III sharesinformation with the engine, hydraulicand transmission controls that can beused during servicing to simplifyservice and troubleshooting.

• Gauges

Display engine coolant, transmission oiland hydraulic oil temperatures, engineoil pressure and fuel tank level.

• Tachometer/Speedometer

Display engine speed and gear indicator.

• Alert Indicators

Include charging system, parking/secondary brake, supplemental steering,brake oil pressure, engine coolant flowand transmission filter status.

6 Floor-Mounted Hydraulic Pilot BladeControls. Are adjustable fore and aft, witha height-adjustable armrest so operatorsof any size can find a comfortableoperating position. A single joystickcontrol allows operator to controlblade functions: lift/lower, tip and tilt.An integrated switch allows single ordual-tilt operation.

Torque Converter Lock-up Clutch.Is activated when the operator pressesa switch on the console. The 844Hautomatically shifts from torqueconverter drive to direct drive when aset speed in second and third forwardor all gears in reverse is reached,providing faster travel speeds andless fuel consumption.

Large Viewing Area. Enhances viewingin all directions. Bonded glass in thefront window eliminates distractingmetal frames with the best operatorvisibility to the blade.

11

Easy Maintenance. In addition to theservicing features built into the engine,the 844H includes:

• Rear Access Stairs. For easy,comfortable access for operatorsand service personnel.

• Large Engine Access Doors.Provide excellent access to servicepoints, engine oil dipstick, diagnosticconnector, engine oil and fuel filters,starting receptacle, air filter indicator,air filters, fuel/water separator and theether starting aid cartridge.

• Large Service Platform. Providespassage to hydraulic filter, fuel fill andtransmission filters through easy-to-open doors.

• Large Door. Provides entrance totransmission and pumps when serviceis required.

• Large Platform Door. Provides accessto fuses and electronic control modules.

• Batteries. Are accessible throughhinged doors in bumper.

• Side Access Doors. On the radiatorguard provide easy access for radiatorcleanout.

• Grouped and Labeled Lube Points.Accessible at ground level, make dailylube maintenance quick and easy.

• Sight Gauges. In the hydraulic tanks,transmission and radiator provide quickcheck for fluid levels.

• Fuses. Automotive-style design areeasy to service.

12

ServiceabilityLess time spent on maintenance means more time on the job.

Machine Selection. Make detailedcomparisons of the machines underconsideration before purchase. Cat dealerscan estimate component life, preventativemaintenance cost and the true cost oflost production.

Purchase. Look past initial price.Consider the financing options availableas well as the day-to-day operatingcosts. Look at dealer services that canbe included in the cost of the machineto yield lower equipment owning andoperating costs over the long run.

Customer Support Agreements.Cat dealers offer a variety of productsupport agreements and work withcustomers to develop a plan that bestmeets specific needs. These plans cancover the entire machine, includingattachments, to help protect thecustomer’s investment.

Product Support. You will find nearlyall parts at our dealer parts counter.Cat dealers use a worldwide computernetwork to find in-stock parts to minimizemachine downtime. Save money withgenuine Cat Reman parts. You receivethe same warranty and reliability asnew products at cost savings of 40 to70 percent.

Operation. Improving operatingtechniques can boost your profits.Your Cat dealer has training videotapes,literature and other ideas to help youincrease productivity.

Maintenance Services. Choose fromyour dealer’s range of maintenanceservices when you purchase your machine.Repair option programs guarantee thecost of repairs up front. Diagnosticprograms such as S•O•SSM and CoolantSampling and Technical Analysis helpyou avoid unscheduled repairs.

Replacement. Repair, rebuild or replace?Your Cat dealer can help you evaluatethe cost involved so you can make theright choice.

13

Complete Customer SupportCat dealer services help keep machines operating longer with lower costs.

14 844H Wheel Dozer specifications

Weights

Operating Weight 70 815 kg 156,120 lb

Transmission

Converter Drive – Forward 1 7 km/h 4.4 mphConverter Drive – Forward 2 12.2 km/h 7.6 mphConverter Drive – Forward 3 21 km/h 13 mphConverter Drive – Reverse 1 7.7 km/h 4.8 mphConverter Drive – Reverse 2 13.4 km/h 8.4 mphConverter Drive – Reverse 3 23 km/h 14.3 mphDirect Drive – Forward 1 7.2 km/h 4.5 mphDirect Drive – Forward 2 12.8 km/h 7.9 mphDirect Drive – Forward 3 22.5 km/h 14 mphDirect Drive – Reverse 1 7.9 km/h 4.9 mphDirect Drive – Reverse 2 14.1 km/h 8.8 mphDirect Drive – Reverse 3 24.8 km/h 15.4 mphNumber of Forward Speeds 3Number of Reverse Speeds 3

• With 45/65 R39 XLD D1 (L4) tires.

• Converter drive two percent rolling resistance.

Hydraulic System

Output at 2,040 rpm and 311 L/min 82 gal/min6900 kPa (1,000 psi)Cylinder, Double-Acting: 209.5 mm � 188 mmTilt and Tip, Bore and Stroke 8.25 in � 7.5 inRelief Valve Setting – 18 650 kPa 2,700 psiBulldozer (Large Pump)Relief Valve Setting – 20 150 kPa 2,920 psiTilt Cylinders (Small Pump)

• Blade control system with double-section vane pump withSAE No. 10 oil at 66° C (150° F).

Steering

Minimum Turning Radius 9910 mm 390 in(Over Tires)Hydraulic output at 2,040 rpm 353 L/min 93 gal/minand 6900 kPa (1,000 psi)Relief Valve Setting 34 500 kPa 5,000 psiSteering Angle 35º

• Full hydraulic load sensing steering system meetsSAE J1511 FEB94 and ISO 5010:1992 specified standards.

Engine

Engine Model Cat C27 ACERT™Gross Power 512 kW 687 hpNet Power 468 kW 627 hpNet Power – Caterpillar 468 kW 627 hpNet Power – EEC 80/1269 468 kW 627 hpNet Power – ISO 9249 468 kW 627 hpNet Power – SAE J1349 (JAN90) 463 kW 621 hpNet Power – DIN 70020 650 PSBore 137 mm 5.4 inStroke 152 mm 6 inDisplacement 27.1 L 1,666 in3

Cylinders 12Torque Rise 31%

• These engine ratings apply at 2,000 rpm when tested underthe specific standard conditions for the specified standard.

• Power rating conditions are based on standard air conditionsof 25° C (77° F) and 99 kPa (29.32 in Hg) dry barometer using35° API gravity fuel having an LHV of 42 780 kJ/kg (18,390 Btu/lb)when used at 30° C (86° F) [ref. a fuel density of 838.9 g/L(7.001 lb/gal)].

• Net power advertised is the power available at the flywheelwhen the engine is equipped with fan, air cleaner, mufflerand alternator.

• No derating required up to 3350 m (11,000 ft) altitude.

0 4 10 14 20 24

Machine Ground Speed (kph)

2 6 8 12 16 18 22

354045

30

25

20

15

10

52

505560

Rim

pull

(kg)

35

40

45

30

25

20

15

10

5

0

Thou

sand

s

Tota

l Res

ista

nce

(%)

(Gra

de +

Rol

ling)

55

60

50

2

3

3L

1L

2L

0 4 8 12 16 20 24 28 32 36 km/h

mph

40

lbs x1000

kg x1000

35

40

30

25

20

15

10

5

0

50

55

45

Torque Converter

Direct Drive

15844H Wheel Dozer specifications

Brakes

Brakes Meets SAE/ISO 3450 1996

Axles

Front FixedRear Oscillating ±11°Maximum Single-Wheel 572 mm 22.5 inRise and Fall

Tires

Tire Choices Several choices availableStandard Tire Size 45/65 R39

• Caterpillar recommends that consulting a tire supplierto evaluate all conditions before selecting a tire model.Other special tires are available on request.

• Tubeless, low-aspect ratio. All steel radial construction forincreased traction and stability, lower rolling resistance.

Operating Specifications

Blade Capacities 15.9-30.7 m3 20.7-40.2 yd3

Ground Clearance 475 mm 1 ft 7 in

Service Refill Capacities

Fuel Tank – Standard 1016 L 268.4 galCooling System 150 L 39.6 galCrankcase 95 L 25 galTransmission 110 L 29 galHydraulic Tank 717 L 189.4 galDifferentials and Final Drives 271 L 71.6 gal– FrontDifferentials and Final Drives 261 L 68.9 gal– RearHydraulic System – Implement 197 L 52 galand Brakes (Tank Only)Hydraulic System – Steering 132 L 34.9 galand Engine Cooling Fan (Tank Only)

Cab

ROPS/FOPS Meets SAE andISO standards

Sound Performance Levels Meets ANSI, SAE andISO standards

• Cat cab with integrated Rollover Protective Structure/FallingObject Protection System (ROPS/FOPS) is standard.

• Standard air conditioning system contains environmentallyfriendly R134a refrigerant.

• ROPS meets SAE J1040 APR88 SAE J394 and ISO 3471:1994.

• FOPS meets SAE J231 JAN81 and ISO 3449:1992 Level IIcriteria.

• The operator sound exposure Leq (equivalent soundpressure level) measured according to the work cycleprocedures specified in ANSI/ASAE J1166 OCT98 is72 dB(A), for the cab offered by Caterpillar, when properlyinstalled and maintained and tested with the doors andwindows closed.

• Hearing protection may be needed when operating withan open operator station and cab (when not properlymaintained or doors/windows open) for extended periodsor in noisy environment.

• The exterior sound pressure level for the standard machinemeasured at a distance of 15 m (49.2 ft) according to the testprocedures specified in SAE J88 JUN86, mid-gear-movingoperation, is 82 dB(A).

• The sound power level is 116 dB(A) measured accordingto the dynamic test procedure and conditions specifiedin ISO 6395:1988/Amd. 1:1996 for a standard machineconfiguration.

• For “CE” marked configurations, the labeled soundpower level is 111 dB(A) measured according to the testprocedures and conditions specified in 2000/14/EC.

3512 mm(11' 6")

4723 mm(15' 6")

ROPS5067 mm(16' 7")

475 mm(19")

2300 mm(7' 7")

4600 mm(15' 1")

3615 mm(11' 10")

10 940 mm(35' 11")

16 844H Wheel Dozer specifications

DimensionsAll dimensions are approximate.

Blade Overall Digging Ground Maximum Total OperatingType Capacity Width Height Depth Clearance Tilt Weight WeightSemi-U 15.9 m3 5418 mm 2024 mm 465 mm 1459 mm 829 mm 7273 kg 70 815 kg

20.7 yd3 213.3" 79.7" 18.3" 57.4" 32.6" 16,034 lbs 156,120 lbs

Heavy-dutySemi-U 15.9 m3 5419 mm 2223 mm 477 mm 1372 mm 940 mm 7763 kg 71 298 kg

20.7 yd3 213.3" 87.5" 18.8" 54" 37" 17,100 lbs 157,186 lbs

Coal 30.7 m3 5846 mm 2024 mm 465 mm 1372 mm 940 mm 6273 kg 69 815 kg40.2 yd3 230.2" 79.7" 18.3" 54" 37" 13,830 lbs 153,916 lbs

Semi-U Blade: This unit combines the characteristics of the S and U blades into one package. It has increased capacity by the addition ofshort wings which include only the dozer end bits.

Blade Specifications

17844H Wheel Dozer specifications

Standard EquipmentStandard equipment may vary. Consult your Caterpillar dealer for details.

Power TrainCat C27 MEUI engine with ACERT™ TechnologyAir-to-Air Aftercooling System (ATAAC)ADEM™ IV ControllerBrakes

Parking: Dry, multi-disc brake; transmission mounted,Service/Secondary: enclosed, wet, multi-disc brakeat each wheel

Electric fuel priming aidImpeller Clutch Torque Converter with lockup clutchPrecleaner/ejectorRemote-mounted hydraulic engine fanSeparated cooling systemSound suppressed mufflerSupplemental steeringTransmission

533 mm (21 in) planetary power shift (electronic)3-speed forward/3-speed reverse

Other Standard EquipmentBackup alarmDrawbar hitch with pinFenders (front)Fuel coolerHigh speed oil change systemHydraulic oil coolerLocking engine enclosuresPower train/guardRear access stairsVandalism protection and caplocksVenturi stacks

Tires45/65 R39 L-4 (XLDDIA), MichelinContact your Cat dealer for more options.

ElectricalAlternator, 95-ampereConverter, for 12-volt accessoriesDiagnostic connector for starting and charging systemsElectric starter (heavy-duty)Electrical system, 24-voltExternal lighting system, front and rearMaintenance-free batteriesStarting receptacle for emergency starting

Operator EnvironmentAir conditioner, R134a refrigerantCab with sound suppressionComfort Series Seat with air suspensionCigar lighter and ashtrayCoat hookComputerized Monitoring System

Action alert system, three-categoryGauges:

tachometerfuel levelhydraulic oil temperaturetransmission oil temperatureengine oil pressurecoolant temperature

Dome light (cab)Electric hornExternal two-post ROPS structureHeater and defrosterIntegrated joystick blade controlLoad-sensing steeringQuick-shift featureRadio-ready cab for entertainment or two-way radio

(three-point mounting)Rearview mirrorsRetractable seat belt 76 mm (3 in) wideFloor mounted hydraulic controlsSight gauges

Hydraulic oil, engine coolant and transmissionSTIC Control Steering SystemStorage for lunch box, cupSunshade/visor, front and rearThrottle lockTinted glassTrainer’s seat with seatbeltTransmission gear indicatorWet-arm wiper/washers, front and rear

18 844H Wheel Dozer specifications

kg lb

Blades

Semi-U 7273 16,034

HD Semi-U 7763 17,114

Coal U-Blade 9542 21,036

Electrical

Lights – Engine Compartment

HID Lights 59 130

Product Link 11 24

Radio – AM/FM Cassette

Rotating Beacon

Rear Vision Camera 12 26

Starting Aids

Diesel Fuel Heater 0

Engine Coolant Heater – 120 volt

Engine Coolant Heater – 140 volt

Starting, Cold Weather 161 355

kg lb

Fuel System

Fast Fuel

Access

Left Side Stairway 430 948

Front Walkway 178 392

Roading Fenders 920 2,208

Miscellaneous

Sound Suppression 1175 2,590

Cab Precleaner

Autolube System – Electric

Case Drain Filtration 64 141

Cooling – High Ambient

Tires

Contact your Order Coordinator for current tire options and availability.

Optional Equipment

2 4

5 11

00

00

2 4

4 9

1 2

9 20

7 15

7 15

844H Wheel Dozer specifications 19

Notes

R

For more complete information on Cat products, dealer services,and industry solutions, visit us on the web at www.cat.com

© 2007 CaterpillarAll Rights Reserved

Printed in U.S.A.

Materials and specifications are subject to change without notice.Featured machines in photos may include additional equipment.

See your Caterpillar dealer for available options.

CAT, CATERPILLAR, their respective logos, ACERT, “Caterpillar Yellow” and thePOWER EDGE trade dress, as well as corporate and product identity used herein,

are trademarks of Caterpillar and may not be used without permission.

AEHQ5689-02 (9-07)

Replaces AEHQ5689-01

844H Wheel Dozer