El Tractor Topador de Ruedas 844 se ha diseñado para usar en trabajos exigentes de explanación, es el más grande de la gama de tractores de ruedas Caterpillar y es ideal para trabajar en aplicaciones grandes de minera, generación de corriente eléctrica,la industria de construcción general y donde quiera que se necesiten movilidad y explanación a gran volumen. Brochure, Folleto,Specalog, oroscocatt, oroscocat

1. ®
844
Wheel Dozer
Blade Capacities 15.9 to 30.7 m3
20.7 to 40.2 yd3
Operating Weight 69 227 kg 152,619 lb
Cat®
3412E HEUI Engine
Gross Power 503 kW 675 hp
Flywheel Power 466 kW 625 hp

2. 2
844 Wheel Dozer
Strong power train combined with a heavy-duty front frame provides long life and
economical operation.
Engine
The Caterpillar 3412E Hydraulic
Electronic Unit Injection (HEUI) engine
delivers power and efficiency in the
most demanding applications. Engine
performance and decreased fuel
consumption are achieved through the
HEUI fuel system. pg. 4
Power Train
The Caterpillar planetary power shift
transmission and Impeller Clutch
Torque Converter with lockup clutch
provide smooth, consistent shifting with
rimpull control and direct drive
efficiency. pg. 4-5
Structures
The 844 features a box-section rear
frame and four-plate front frame
providing strength and stability.
Together they provide resistance to
dozing shocks and stresses while
absorbing shock loads and twisting
forces. pg. 6
Engineered for demanding work in large
dozing applications. The 844 Wheel Dozer
joins the Caterpillar®
wheel dozer line-up
as an ideal match for power generating
utilities, smaller scale mines and the
general contracting industry.

3. 3
Blades and Blade Control
Choose between 21 and 40 yd3 semi-U,
heavy-duty semi-U and coal blades.
Replaceable bolt-on cutting edges and
bottom wear plates help extend blade
life. A single lever is used to
hydraulically control all blade
operations. pg. 10-11
Hydraulics
Two, independent hydraulic systems
and load-sensing steering are the
invisible force behind the mobility and
versatility of the 844.
pg. 7
Operator Station
Experience a high level of efficiency
and comfort with one-hand operation
provided by the STIC controller and a
state-of-the-art cab. Operator
productivity is also increased with
improved range of viewing, reduced
sound levels, improved ventilation and
easy entry and exit.
pg. 8-9
Serviceability
Large engine doors, rear access stairs,
and convenient service platform with
large doors enhance the serviceability
of the 844. pg. 12

4. 4
Power Train
844 power train components deliver dependable, reliable performance customers expect
from Cat wheel dozers.
The Caterpillar 3412E Hydraulic
Electronic Unit Injection engine is rated
at 466 kW Net (625 hp) at 2000 rpm.
HEUI fuel system and Electronic
Control Module (ECM) deliver power
and efficiency in the most demanding
applications. Electronic control
provides many benefits:
s Automatic altitude deration
s Elevated low idle
s Cold weather starting mode
s Acceleration delay on startup to
reduce engine wear
s Advanced diagnostic capabilities
s Automatic control of ether aid
Complete control of injection timing
without concern for cam profile
limitations. Complete control of
engine speed provides advantages in
lower emissions, quieter operation,
reduced smoke, improved hot or cold
starting, white smoke cleanup and
high altitude operation.
Complete control of injection
duration. The HEUI system will
decrease proportionately with engine
speed but can also electronically
control the oil supply pressure. This
provides improved engine
performance and decreased fuel
consumption.
Injection rate shaping reduces nitrous
oxide (NOx) emissions and reduces
engine combustion noise.
1 Aftercooler lowers inlet charge
temperature. Reduces thermal stresses
that can cause premature wear of
pistons, rings and liners.
2 High injection pressures,
independent of engine speed,
decrease smoke and emissions while
improving response.
3 Oil-cooled pistons and full-length,
water-cooled cylinder liners provide
maximum heat transfer for longer
component life.
4 Engine oil cooler maintains optimum
oil temperature for proper cooling
and lubrication.
s Engine cooling provided by Multi-
Row Modular radiator. Hydrostatic
fan drive gives the standard cooling
package 110°F ambient capability.
4
3
2
1

5. 5
3 533 mm (21") planetary, electronic,
power shift transmission. This is the
same transmission found in the 990
Series II wheel loader. Electronic
shifting provides smooth consistent
shifts with finger tip controls housed
in the STIC controller. The
transmission is built around a center
shaft with a gear set cluster stacked
end-to-end to distribute load,
conserve space and transfer energy
efficiently. Large diameter perimeter
clutches coupled with high contact
planetary gear sets provide high
torque carrying capacity for long,
trouble-free life.
Axle-shaft, oil-disc brakes are fully
hydraulic, completely sealed and never
need adjustment. Disc face grooves
provide cooling even when brakes are
applied for a long, fade resistant life.
s This design provides larger cooling
oil reservoir and thicker separator
plates than conventional brake
designs. This gives the brake higher
heat dissipation rates giving it higher
capacity than conventional oil-disc
brakes.
s The location of the brake reduces
service time. Conventional brakes
require final drive disassembly. The
axle-shaft brake design allows brake
service while leaving the final drive
intact. Reduced service time and
machine downtime keeps operating
costs low.
s Bevel gear sets and differentials are
common with the 990 Series II wheel
loader.
Impeller Clutch Torque Converter
allows the operator to modulate rimpull
from 100 percent to 20 percent of
maximum rimpull. After 20 percent of
maximum rimpull is achieved, further
pedal travel applies the brake. The
torque converter is equipped with a
lockup clutch for direct drive efficiency.
1 Impeller clutch. Locked in fully
engaged position for maximum
engine power transfer.
2 Lockup clutch. Provides direct drive
efficiency in all three gears with
higher speeds and improved fuel
economy on long distance dozing.
2 1 3

6. 6
Structures
Advanced design and materials provide superior strength.
Structures on the 844 are more than 90
percent robotically welded. This
provides highly consistent welds with
deep plate penetration and excellent
plate fusion. The benefit is greater
fatigue strength and longer life than
with conventional welding methods.
Castings in the engine end-frame are
used in critical high-stress areas to help
spread the load and reduce the number
of parts. The casting for the rear
trunnion mount also serves as an engine
mount, which provides a load path for
the weight and torque of the engine to
travel down to the trunnion and then on
through to the axle. Other castings used
in the engine-end frame include: front
trunnion mounts, steering cylinder
brackets, articulation stops and lock
link.
1 Box-section rear frame absorbs shock
loads and torsional forces, solidly
maintaining alignment for hitch pins
and driveline.
2 Four-plate front frame provides
maximum structural strength to resist
twisting loads during dozing
applications.
3 Upper and lower hitch pins pivot on
double-tapered roller bearings and are
shaped to direct stress away from the
end of the weld, resulting in a
smoother transition of stress loads.
4 Spread-hitch design helps square up
the frame and provides more
clearance for hydraulic lines. Double
tapered roller bearings and hardened
pins resist both horizontal and
vertical loads to increase life. The
spread hitch also makes service
access easier.
Engine and transmission mounts are
designed to use mushroom and cup-
shaped ISO mounts, reducing
component vibration and sound levels.
The engine mounts directly to the rear
cross member, simplifying and
improving load transfer structure.
1
2
3
4

7. 7
1 Two separate, hydraulic systems.
One system is for implements and
brakes while the other is for steering
and hydraulically-driven engine
cooling fan. The benefits of the
separate hydraulic systems are
increased cooling and elimination of
cross-contamination. If one system
runs hot or is contaminated, the other
will be unaffected.
2 Blade control. Armrest-mounted
control lever sends signals to a pilot
valve for tilt/tip control and to a main
valve for lift control.
s Tandem vane pumps provide
hydraulic flow for the lift, tilt and tip
functions. The circuit is well balanced
to provide control when all functions
are used simultaneously.
s Well-proven pumps, valves and
cylinders are common with those
used on large, Caterpillar track-type
tractors.
s For improved serviceability, all
hydraulic pumps are mounted on a
single pump drive.
3 Load Sensing Steering with STIC
Control System is a revolutionary
system that integrates steering and
transmission into a single controller.
The variable displacement pump
maximizes machine performance by
directing power through the steering
system only when needed. More
efficient use of power results in
decreased fuel consumption and
higher production.
s Simple side-to-side motions of the
operator’s left arm turn the machine
right or left.
s Transmission shifting forward,
neutral, or reverse is controlled by the
operator’s fingers, and gear selection
is controlled by the operator’s thumb.
Caterpillar‘s XT-3 and XT-5 hose, O-ring
face seals and large-bore lift and tilt
cylinders top off the hydraulic system,
delivering the performance and
durability owners expect. Reliable
components reduce leaks and help
protect the environment.
Hydrostatic cooling fan is used for
engine, transmission and hydraulic
cooling. A variable displacement pump
drives the fan’s hydraulic motor so that
fan speed varies with rpm. The fan
draws only the power needed for
cooling, reducing fuel consumption and
increasing efficiency.
1
3
2
Hydraulics
Well-balanced hydraulics deliver precise low-effort control and trouble-free operation.
2

8. 8
6
7
2
3
1
Operator Station
Comfort and control — top quality operator station will help maximize productivity.

9. 9
Spacious cab design, incorporating
innovations for operator comfort and
productivity, include excellent viewing
area, interior sound levels below 75
dB(A), Caterpillar Contour Series seat,
standard coat hook, cup holder, storage
bin, sun visor, intermittent wet-arm
wipers, and is radio-ready for two-way
radios.
1 STIC Control System is a
revolutionary system that integrates
steering and transmission into a
single controller. Simple side-to-side
motions of the operator’s left arm
turn the machine right or left.
Transmission shifting forward,
neutral or reverse is controlled by the
operator’s fingers, and gear selection
is controlled by the operator’s
thumb. These factors combine to
produce a fluid motion that reduces
effort and allows the operator to
work the machine for long periods of
time with little or no fatigue.
2 Left foot pedal operates Impeller
Clutch Torque Converter for about
the first inch of travel, then engages
the brakes. Within the first inch of
pedal travel, rimpull can be
controlled from 100 percent to 20
percent.
3 Contour Series seat with air
suspension and retractable seat belt
is designed for comfort and support.
Seat cushions reduce pressure on the
lower back and thighs while
allowing unrestricted arm and leg
movement. The seat has three height
levels. The retractable seat belt
remains off the floor and is easy for
the operator to reach.
4 Quick-shift feature allows quicker
cycle times by shifting from 1st
forward to 2nd reverse.
5 Throttle lock allows operator to
preset the engine speed and
concentrate on productivity. The
throttle lock can be deactivated by
pressing the brake pedal.
6 Computerized Monitoring System
(CMS) uses a vacuum fluorescent
display allowing gauges to be easily
read in direct sunlight or at night.
The three category operator alert
system is retained as part of the
CMS. In addition, the system
provides four diagnostic modes,
resulting in easy system
troubleshooting and minimum
downtime.
7 Seat-mounted hydraulic blade
controls are attached to the right
side of the seat. They are adjustable
fore and aft, with a height-adjustable
armrest so that operators of any size
can find a comfortable operating
position. Single lever control allows
operator to control blade functions:
lift/lower, tip and tilt. Switch control
on top of control lever allows option
of single or dual-tilt operation.
8 Torque converter lockup clutch is
activated when operator presses a
switch on the console. The 844
automatically shifts from torque
converter drive to direct drive when
a set speed in each gear is reached,
providing faster travel speeds and
less fuel consumption.
Large, viewing area enhances viewing
in all directions. Bonded glass in the
front window eliminates distracting
metal frames with the best operator
visibility to the blade.
5
4
8

10. 10
Heavy-duty blade linkage is common
with a Caterpillar D9 Track-Type
Tractor. These well-proven components
are designed for tough applications.
s Lift cylinders raise and lower blade
for efficient dozing action.
s Two position tilt cylinder mounting
for increased flexibility for various
applications.
s Cutting edges are DH-2 steel. End
bits are DH-3 to provide maximum
service life in tough materials.
s Trunnions, pusharms and tag link are
sized for large dozing loads.
Single-lever blade control hydraulically
operates blade raise, lower, tilt and tip.
Lift circuit features:
s Four positions: raise, hold, lower and
float
s Detente hold on float
Tilt/tip circuit features:
s Operator selected single or dual-tilt
s Finger tip control for tip operation
Low-effort control:
s Single-lever implement control
s Seat mounted controls
s Pilot operated tilt/tip for lower lever
effort
Operator has the option of either single
or dual-tilt operation by using a switch
located on top of control lever. A
generous range of tilt motion enables
excellent control for dozing.
Blade Control
Well-proven Cat components deliver dependable service and ease of operation.

11. 11
Resilient and durable Caterpillar blades
are designed with excellent dozing and
rolling characteristics.
s Capacities and widths are set to
achieve increased productivity.
s Special design allows for spreading
of cover material as well as dozing of
heavier loads.
s High-strength, pressed rib
construction.
s Large, Caterpillar track-type tractor,
bolt-on cutting edges and bottom
wear plates.
s Fitted with Caterpillar standard
hardware and Ground Engaging
Tools (G.E.T.).
s Rebuildable for long blade life.
1 Coal blade is designed for precise and
productive dozing while helping to
retain load control with increased
capacity for lighter materials.
s Wing angles help retain the load
while dozing.
2 Semi-U blade combines the
characteristics of the S and U blades
into one package.
s Increased capacity with the
addition of short wings, which
include only the dozer end bits,
without sacrificing spreading
characteristics of straight blades.
The heavy-duty semi-U blade has the
same configuration as the semi-U blade,
but it is built with thicker plates for
more severe applications.
Blades
Caterpillar blades are built to handle tough applications.
1
2

12. 12
Easy maintenance. In addition to the
servicing features built into the engine,
the 844 includes:
s Rear access stairs for easy,
comfortable access for operators and
service personnel.
s Large engine access doors provide
excellent access to service points,
engine oil dipstick, diagnostic
connector, engine oil and fuel filters,
starting receptacle, air filter indicator,
air filters, fuel/water separator and the
ether starting aid cartridge.
s Large service platform provides
passage to hydraulic filter, fuel fill
and transmission filters through easy-
to-open doors.
s Large door provides entrance to
transmission and pumps when service
is required.
s Large door in platform provides
access to fuses and electronic control
modules.
s Batteries are accessible through
hinged doors in bumper.
s Side access doors on the radiator
guard provide easy access for radiator
cleanout.
s Grouped and labeled lube points,
accessible at ground level, make daily
lube maintenance quick and easy.
s Sight gauges in the hydraulic tanks
and radiator provide quick check for
fluid levels.
Serviceability
Less time spent on maintenance means more time on the job.

13. 13
Cat Dealers offer a wide range of
services that can be set up under a
customer support agreement when
purchasing equipment. The dealer will
help customers choose a plan that can
cover everything from machine and
attachment selection to replacement, to
help get the best return on the machine
investment.
Selection. Make detailed comparisons
of the machines under consideration
before buying. How long do
components last? What is the cost of
preventive maintenance? What is the
true cost of lost production? Cat Dealers
can give precise answers to these
questions.
Operation. Improving operating
techniques can boost one’s profits.
Cat Dealers have training videotapes,
literature and other ideas to help
increase productivity.
Maintenance. More and more
equipment buyers are planning for
effective maintenance before buying
equipment. Choose from the dealer’s
wide range of maintenance services at
the time of purchase. Repair option
programs guarantee the cost of repairs
up front. Diagnostic programs such as
S•O•S oil analysis and Technical
Analysis help avoid unscheduled
repairs.
Product support. Nearly all parts are
available at the Cat Dealer parts
counter. Cat Dealers utilize a worldwide
computer network to find in-stock parts
to minimize machine downtime. Save
money with remanufactured parts and
receive the same warranty and
reliability as new products at cost
savings of 40 to 70 percent.
Replacement. Repair, rebuild or
replace? Cat Dealers can help evaluate
the cost involved so the right choice is
made.
Complete Customer Support
Cat Dealer services help keep machines operating longer with lower costs.

14. 14 844 Wheel Dozer specifications
Engine
Four-stroke cycle, twelve cylinder, turbocharged, aftercooled 3412E diesel engine.
Ratings at 2000 rpm* kW hp
Gross power 503 675
Net power 466 625
The following ratings apply at 2000 rpm
when tested under the specific standard
conditions for the specified standard:
Net Power kW hp PS
Caterpillar 466 625 —
EEC 80/1269 466 625 —
ISO 9249 466 625 —
SAE J1349
(JAN90) 461 618 —
DIN 70020 — — 648
Dimensions
Bore 130 mm 5.4 in
Stroke 152 mm 6.0 in
Displacement 27 liters 1649 in3
Features
s high pressure injectors
s full electronic control
s parallel manifold porting with two
intake and two exhaust valves per
cylinder. Stellite-faced valves, hard
alloy steel seats and valve rotators
s cam-ground and tapered, aluminum-
alloy pistons with three keystone
designed rings, each cooled by oil
spray
s steel-backed, copper-bonded,
aluminum bearings, through-hardened
crankshaft journals
s pressure lubricated with full-flow
filtered and cooled oil
s dry-type air cleaner with primary and
secondary elements
s direct-electric 24-volt starting system,
75-amp alternator and two, 12-volt
190-amp-hour batteries
s engine/torque divider module is
isolation mounted to the main frame
reducing machine vibration and
structure-radiated noise
s water cooled turbocharged bearing for
longer life
Transmission
21" planetary power shift transmission
with three speeds forward and reverse.
Maximum speeds, forward and reverse,
with 45/65 R39 XLD D1A - Type A (L4)
tires:
km/h mph
Forward 1 7.2 4.5
2 12.9 8.0
3 22.5 14.0
Reverse 1 8.2 5.0
2 14.2 8.8
3 25.0 15.5
Features
s electronic shift control
s self diagnostics accessible through
Computerized Monitoring System
s quick-shift feature
s controls for electric shift transmission
are housed in STIC controller
s Impeller Clutch Torque Converter is
standard with lockup in all three gears
Power rating conditions
s based on standard air conditions of
25°C (77°F) and 99 kPa (29.32 in Hg)
dry barometer
s used 35° 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)]
s net power advertised is the power
available at the flywheel when the
engine is equipped with fan, air
cleaner, muffler and alternator
s no derating required up to 2286 m
(7,500 ft) altitude
35
40
45
50
55
60
30
25
20
15
10
5
0
100
110
120
130
140
70
80
90
60
50
40
30
20
10
0
lbs x
1000
kg x
1000
0
GRADEABILITY-PERCENT
(Grade+RollingResist)
3rd Gear
1st Gear
1st Gear
2nd Gear
3rd Gear
2nd Gear
844
Rimpull
vs.
Ground Speed
30
25
40
35
45
20
15
10
5
0 4 8 12 16 20 24 km/h
0 2 4 6 8 10 12 14 16 mph
Speed
Rimpull
Torque Converter Direct Drive

15. 15844 Wheel Dozer specifications
Cab
Integrated Rollover Protective Structure
(ROPS) is standard.
Features
s meets OSHA and MSHA limits for
operator sound exposure with doors
and windows closed (according to
ANSI/SAE J1166 MAY90)
s ROPS meets the following criteria:
- SAE J394
- SAE 1040 APR88
- ISO 3471-1986
s also meets the following criteria for
Falling Objects Protective Structure
(FOPS):
- SAE J231 JAN81
- ISO 3449-1984
s ROPS structure is certified for
84 286 kg (185,650 lb) operating
weight
s standard machine meets CE 89/392
safety directive, and CE 86/662
spectator (ISO 6393) and operator
(ISO 6394) sound requirements
NOTE: When properly installed and
maintained, the cab (tested with doors and
windows closed according to ANSI/SAE
J1166 MAY90) meets OSHA and MSHA
requirements for operator sound exposure
limits in effect at time of manufacture. The
operator sound pressure level is 75 dB(A)
when measured per ISO 6394 or
86/662/EEC.
Final Drives
Planetary final drive consists of a ring
gear, 3 planet gears and planet gear
carrier, and a sun gear.
Features
s ring gears splined to axle housing
s proprietary gear cutting and heat treat
methods used in the manufacture of
components
s full-floating bronze sleeve bearings
used on planet gears
s oil-bath lubrication of final drive
Axles
Fixed front, oscillating rear (±11°).
Features
s maximum single-wheel rise and fall
572 mm (22.5")
s bevel gear set and differentials
s Duo-Cone seal between axle hub and
housing
s axle shaft brakes
s use SAE 30 or 40W (depending on
temperature) (oil change interval
every 2000 hours or 1 year)
Brakes
System meets SAE/ISO regulations.
Service brake features
s fully hydraulic, completely enclosed
and sealed, oil-disc brakes
s adjustment free
s separate circuits for front and rear
axles
s high capacity axle-shaft design
s easy access for service
s dual pedal braking
Parking brake features
s multiple-disc, oil-enclosed brake
s located on transfer gear case output
shaft
Secondary brake features
s Computerized Monitoring System
alerts operator if pressure drops below
875 psi (6035 kPa) and automatically
applies parking brake
s manual override possible to allow
movement of machine
Tires
Tubeless, low-aspect ratio. All steel
radial construction for increased traction
and stability, lower rolling resistance.
Tire choices
s 45/65 R39 L-4 (XLDDIA), Michelin
s 40.5/75 R39 1-Star, Goodyear
NOTE: Caterpillar recommends that you
consult a tire supplier to evaluate all
conditions before selecting a tire model.
Other special tires are available on request.
Monitoring System
Computerized Monitoring System uses
technology to make a dramatic
difference in operator efficiency,
machine productivity and availability.
Features
s gauges display engine coolant
temperature, transmission oil
temperature, engine oil pressure,
hydraulic oil temperature and fuel
tank level
s tachometer/speedometer displays
engine speed and gear indicator
s alert indicators include: charging
system, parking/secondary brake,
supplemental steering, brake oil
pressure, engine coolant flow and
transmission filter status

16. 16 844 Wheel Dozer specifications
Implement system with double-section vane pump
Output at 2126 rpm and 6894 kPa (1000 psi)
with SAE (No 10 oil at 66°C 150°F) 342 L/min 89 gpm
Cylinders, double-acting:
lift, bore and stroke 133.5 mm x 1535 mm 5.25" x 60.5"
Cylinder, double-acting:
tilt and tip, bore and stroke 209.5 mm x 188 mm 8.25" x 7.5"
Relief valve setting
Bulldozer (large pump) 18 650 kPa 2700 psi
Tilt cylinders (small pump) 20 150 kPa 2920 psi
Implement Hydraulic System
Completely sealed system with innovative low-effort controls.
Features (standard)
s completely enclosed system
s two independent systems. One for
steering and hydraulically-driven
engine cooling fan, one for
implements and brakes
s Cat built main implement pumps
s Caterpillar’s XT-3, XT-5 hose used
on entire machine except pilot lines in
cab
s full-flow filtering
s reusable couplings with O-ring face
seals
Service Refill Capacities
U.S.
L Gallons
Fuel tank–standard 930 245
Cooling system 183 47.5
Crankcase 50 13
Transmission 70 18
Hydraulic tank 541 141
Differentials and final drives
Front 218 56.5
Rear 218 56.5
Hydraulic system
Implement and brakes
Tank only 174 45
Steering and engine cooling fan
Tank only 129 33.5
Min. turning radius
(over tires) 9910 mm 32' 6"
Hydraulic output at 2128 rpm
and 1000 psi (6900 kPa)
410 L/min 108 gpm
Relief valve setting
31 005 kPa 4500 psi
Features
s STIC control steering system
s center-point frame articulation
s front and rear wheels track
s hydraulic power with efficient, load-
sensing system
s variable displacement piston pump
s steering angle of 35º in each direction,
one-hand operation
s full flow filtering
Steering
Full hydraulic load sensing steering system meets SAE J1511 FEB94 and ISO 5010:
1992 specified standards.

17. 17844 Wheel Dozer specifications
844
ROPS
5142 mm
(16' 9")
4600 mm
(15' 1")
10 940 mm
(35' 9")
2300 mm
(7' 7")
3471 mm
(11' 5")
552 mm
(22")
3469 mm
(11' 5")5185 mm
(17' 0")
Dimensions
All dimensions are approximate.
NOTE: Dimensions vary with blade. Refer to blade specifications chart on page 18.

18. 18 844 Wheel Dozer specifications
Blade Overall Digging Ground Maximum Total Operating
Type Capacity Width Height Depth Clearance Tilt Weight Weight
Semi-U 15.9 m3 5418 mm 1813 mm 465 mm 1459 mm 829 mm 7273 kg 69 227 kg
20.7 yd3 213.3" 71.4" 18.3" 57.4" 32.6" 16,034 lbs 152,619 lbs
Heavy-duty
Semi-U 15.9 m3 5278 mm 1877 mm 609 mm 1372 mm 940 mm 7763 kg 69 717 kg
20.7 yd3 207.8" 73.9" 24" 54" 37" 17,100 lbs 153,685 lbs
Coal 30.7 m3 5846 mm 2289 mm 609 mm 1372 mm 940 mm 6273 kg 68 227 kg
40.2 yd3 230" 90" 24" 54" 37" 13,830 lbs 150,415 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 of
short wings which include only the dozer end bits.
Blade Specifications
Blade Controls
Mechanical operated raise/lower circuit.
Pilot operated tilt/tip circuit.
Lift circuit features
s four positions: raise, hold, lower and
float
s detente hold on float
Tilt/tip circuit features
s operator selected single or dual tilt
s finger tip control for tip operation
Control
s single-lever implement control
s seat mounted controls
s pilot operated tilt/tip for lower lever
effort

19. 19844 Wheel Dozer specifications
Standard Equipment
Standard and optional equipment may vary. Consult your Caterpillar Dealer for specifics.
Electrical
Alternator, 105-ampere
Converter, for 12-volt accessories
Diagnostic connector for starting and
charging systems
Electric starter (heavy-duty)
Electrical system, 24-volt
External lighting system, front and rear
Maintenance-free batteries
Starting receptacle for emergency
starting
Operator environment
Air conditioner, R-134A refrigerant
Contour Series Seat with air suspension
Cigarette lighter and ashtray
Coat hook
Computerized Monitoring System
Action alert system, three-category
Gauges:
tachometer
fuel level
hydraulic oil temperature
transmission oil temperature
engine oil pressure coolant
temperature
Dome light (cab)
Electric horn
External two-post ROPS structure
Heater and defroster
Load-sensing steering
Quick-shift feature
Radio-ready cab for entertainment or
two-way radio (three-point mounting)
Rearview mirrors (interior and exterior
mounted)
Retractable seat belt 76 mm (3") wide
ROPS cab with sound suppression
Seat-mounted hydraulic controls
Sight gauges, hydraulic oil and engine
coolant
Single-lever blade control
STIC Control System
Storage for thermos, lunch box, cup
Sunshade/visor, front and rear
Throttle lock
Tinted glass
Transmission gear indicator
Wet-arm wiper/washers, front and rear
Power train
Cat 3412E HEUI engine
Fuel priming aid
Full hydraulic, enclosed, wet multiple-
disc service brakes and
parking/secondary
Impeller Clutch Torque Converter with
lockup clutch
Precleaner/ejector
Remote-mounted hydraulic engine fan
Separated cooling system
Sound suppressed muffler
Supplemental steering
Swing-out cooler cores
Transmission,
21" planetary power shift (electronic)
3-speed forward/3-speed reverse
Other standard equipment
Backup alarm
Drawbar hitch with pin
Fenders (front and rear)
Hydraulic oil cooler
Muffler
Lighting, general purpose (four)
Locking engine enclosures
Power train/guard
Rear access stairs
Vandalism protection and caplocks
Tires
45/65 R39 L-4 (XLDDIA), Michelin
kg lb
Blades
Semi-U 7273 16,034
Heavy-duty Semi-U 7763 17,100
Coal 6273 13,830
Fuel system 1 3
High Ambient Cooling Arrangement 60 132
Oil change system 5 11
kg lb
Quarter panel wiper washer 17 38
Starting aids
Cold weather starting system 180 396
Diesel fuel heater 4 9
Heater, engine coolant 3 7
Tires – 40.5/75 R39 1-Star, Goodyear -1030 -2,272
Optional Equipment
With approximate changes in operating weights.

20. 844 Wheel Dozer
AEHQ5307 (3-98)
Materials and specifications are subject to change without notice.
Featured machines in photos may include additional equipment.
See your Caterpillar Dealer for available options.
www.CAT.com
© 1998 Caterpillar
Printed in U.S.A.