637G^Non-Current

Legroom

A new design increases legroom 11%, a full 88.9 mm (3.5 in), and eliminates knee contact points.

Standard Enclosed ROPS

Standard enclosed ROPS with air conditioning enhances operator comfort as well as efficiency.

Multi-Adjustable Seat

The Cat Comfort Cloth Seat offers comfort with multi-adjustable seat and armrests.
• Swivels and locks in four positions (0º to 30º) providing the optimum operating position in the cut or on the haul.
• Fore/aft and vertical height adjustment to accommodate various sized operators.

Joystick Controller

Simple and easy to operate, the joystick enhances the productivity of operators of all skill levels. Requires less force to control the critical scraper functions and requires less lever travel.1) Bowl (forward & back)2) Ejector (side to side)3) Apron (thumb rocker switch)4) Transmission Hold5) Cushion Hitch6) Trigger (not shown - is on front of joystick) • Push-Pull (bail up/down)* Standard open bowl does not have a trigger.

Instrument Display Panel

Instrumentation has been relocated for optimal viewing. Real-time performance and diagnostic information is provided through the display panel.

Electronic Monitoring System (EMS)

Monitors the machine status and provides real-time information including warnings of problems identified by the EMS.

Ergonomic Switch Layout

Enhances convenience by placing the frequently used switches and indicator lights on the instrument panel, and less frequently used switches on the overhead console.

Throttle Lock Controller

Enhances operation during long haul cycles by allowing the operator to maintain a desired engine speed without maintaining pressure on the throttle.

Standard Air Conditioning

Standard air conditioning system with improved ventilation location enhances airflow in the cab.

Storage And Amenities

Convenient storage location includes space for a lunch box and first aid kit. The cab also has a cup holder as well as an ashtray.

Visibility

The redesigned hood has sloped corners to maintain visibility. The exhaust has been moved to the back of the hood to increase visibility to the right side.

Air Filter Restrictor Indicator

Electronic control module monitors air filter restriction and sends a warning message to the electronic monitoring system to alert the operator if the restriction exceeds the allowable limit.

Automatic Ether Injection

Electronic control module activates the ether injection system during engine cranking to enhance cold weather starting.

Automatic Altitude Compensation

At high altitudes the system automatically de-rates fuel delivery as a function of barometric pressure sensed by the system's atmospheric pressure sensor.

Easy Access Diagnostics

Electronic Technician displays real-time pressures, temperatures, fuel settings and diagnostic messages as well as historical information such as engine over-speeds, overheating, low oil pressure, and air filter restriction events.

Fuel Economy

Electronic controls yield a fuel savings by optimizing the timing setting for varying conditions.

Greater Reliability

Caterpillar's HEUI™ fuel system uses hydraulic electronic unit injectors, has fewer moving parts than mechanical unit injection, and requires few adjustments.

Maintenance

With fewer mechanically controlled parts to wear or adjust, the electronic controls reduce maintenance costs and increase machine availability.

Reduced Exhaust Smoke

Utilizing electronic sensors, the optimum air/fuel ratio is precisely controlled by the electronic control module during all segments of the haul cycle. This results in a reduction of smoke and particulates during cranking, starting, and acceleration.

Low Battery Elevated Idle

Electronic control module automatically compensates for low alternator output at low idle to keep the batteries fully charged.

Integrated Electronics

Electronic controls integrated into the power train monitors the engine, transmission, and operator input.
• Electronic control provides smooth, consistent shifts through the synchronization of engine and transmission speeds.
• Planetary design provides larger contact area between gears than countershaft transmissions for greater load-carrying capacity.

Controlled Throttle Shifting

Automatically synchronizes engine speed to transmission speed during shifting to reduce power train stress, increase component life, and provide a smoother ride for the operator.

Programmable Top Gear Selection

Top gear selection may be either selected by the operator or downloaded into the MAC-14 controller. Provides the flexibility to match the hauling speed of the fleet to specific job-site needs.

Differential Control

Electronic differential lock on the tractor helps prevent the drive wheels from spinning in poor underfoot conditions. The operator engages the differential lock, prior to wheelspin, with either the left or right foot controls located on the floor of the cab.

Transmission Hold

Allows the operator to maintain the current gear for enhanced control.

Neutral Coast Inhibitor

Prevents the transmission from shifting into neutral if the operator selects neutral while moving faster than 8 kmph (5 mph). Maintains oil to transmission to prevent damage.

Directional Shift Management

Reduces driveline torque and transmission clutch energy when directional shifts are attempted while the engine is at high rpms.

Final Drives

Outboard-mounted, planetary design final drives reduce torque loads on other drivetrain components while delivering exceptional reliability in the toughest applications.

Braking System

Provides cam-operated expanding-shoe type brakes, independent front and rear circuits, low air pressure audible and visual action alert indicators, and a push-button operated parking brake.

3408E Tractor Engine

The engine has the HEUI™ fuel system which uses hydraulically actuated electronically controlled unit injectors. The 3408E diesel engine has dual horsepower capability for the tractor, and provides the power and torque rise for excellent lugging in tough loading conditions.

Dual Horsepower Capability

The electronic engine provides dual horsepower settings, which increases horsepower and provides quicker acceleration on the haul road.

3306 Scraper Engine

Powered by the 3306 direct-injection diesel engine rated at 250 hp (186 kW). Automatic variable-injection timing delivers fuel as needed when engine speed varies between cut or fill work, and during high-speed hauling for maximum efficiency.

HEUI™ Fuel System

Yields improved fuel economy through more precise fuel delivery and cleaner, more efficient combustion.

Advanced Diesel Engine Management (ADEM)

Utilizes advanced engine management software to monitor, control and protect the engine.

Air To Air After Cooling (ATAAC)

Reduces air inlet temperature for enhanced combustion efficiency, reduced emission levels, higher altitude capability, and more power.

Tractor Transmission

The electronically controlled Caterpillar planetary powershift transmission uses proven components electronically integrated to achieve new levels of performance and efficiency.
• Eight forward and one reverse speed.
• Gears one and two operate in converter drive for increased torque capability during cut and fill operations.
• Gears three through eight operate in direct-drive for drivetrain efficiency during the haul and return.
• Reverse gear operates in converter drive.

Scraper Transmission

Electronically controlled Caterpillar planetary powershift transmission.
• Four forward and one reverse speed.
• All gears operate in converter drive for increased torque capability.
• The scraper transmission is electronically controlled by the tractor transmission and is synchronized to match the tractor transmission gear selection.

Retarder

Reduces wear on the service brakes and enhances machine control. The hydraulic retarder is internal to the power train and acts as an internal brake when going down a grade. It is engaged before going down a grade.

Increased Performance

Dual stage coolant flow process improves cooling capability by allowing coolant to pass on the air side of the radiator as well as the fan side. The coolant travels:
• Into the air side of the bottom tank;
• Up the air side of the core;
• Down the fan side of the core;
• To the fan side of the bottom tank;
• Then back to the engine.

Basic Construction

A modular design radiator that is less prone to plugging due to a lower fin density of nine fins per inch versus thirty-three of the previous folded core radiator.

Improved Serviceability

Modular design allows one module to be replaced instead of replacing the entire radiator.
• Shunt tank incorporates a sight gauge for quick, accurate checks of coolant level.
• No longer necessary to remove the top tank to swap out modules.
• Unique service tool facilitates core removal and allows one-person service job.
• Shunt tank incorporates a sight gauge for quick, accurate checks of coolant level.

Low-profile Design

Offers less resistance to incoming materials.

Cat Bulldozer Ejection

System combines constant spreading control while minimizing carryback material.

Overflow Guard

Helps retain material and keep it from spilling over onto the rear of the scraper.

Cellular Construction

Adds strength and dent resistance to bowl sides and floor.

Caterpillar Ground Engaging Tools (G.E.T.)

To optimize scraper loading in various materials a wide range of G.E.T. are available.

Cutting Edge

May be adjusted according to job conditions. The stinger (drop down) position provides good penetration and efficient flow of material into the bowl while the level cutting edge is used for finish work. For efficient loading the thinnest edge that provides satisfactory wear life should be used.

Material Application

Work alone capability with a wide material appetite ranging from overburden to laminated rock. Conditions material which promotes compaction in the fill and significantly reduces dust during loading.

Dual Horsepower

Provides increased power to the auger for improved loading performance.

Auger Mechanism

The auger lifts material off of the cutting edge for true self-loading capability. Material is distributed evenly throughout the bowl, resulting in consistent loads.

Apron

Prevents material spillage and retains fine material far better than an elevating scraper.

Additional Auger Features

Caterpillar design provides top performance.
• Two-speed auger motor shifts automatically from high speed to low speed to enhance loading capability.
• Dual horsepower tractor engine automatically reverts to the higher setting when the auger motor is engaged.
• Single hydraulic system for entire machine with separate implement pumps and valves.
• Scraper slip limiter switch prevents rear wheel spin during loading.

Material Application

Well suited to handle a wide variety of material from clay to shot rock.

Push-Loading

Working together, push-pull scrapers combine to place over 1,400 horsepower on a single cutting edge. Fast loading means quicker cycle times.

Tandem Engine

Provides the ability to handle steep grades as well as all wheel drive to handle soft, slippery underfoot conditions.

Dual Horsepower

Provides increased horsepower during the haul which results in faster cycle times.

Push-Pull Attachment

Optional push-pull arrangement concentrates the combined horsepower of two machines onto one cutting edge. The push-pull attachment allows two individual machines to act as a self-loading machine. Typically both of the push-pull machines can load in less than a minute.

Cushion Hitch

Electrically actuated hydraulic damper absorbs haul road shocks for increased operator comfort.

Cushion Hitch Features

Designed for precise control.
• Can be locked down when loading or spreading.
• Vertically mounted hydraulic cylinder transfers road shocks to nitrogen accumulators.
• Controlled oil flow dampens rebound oscillation.
• Leveling valve automatically centers piston in cylinder for all loads.
• Extensive use of steel castings eliminates many welded joints and increases strength.
• Double-kingbolt design withstands high external forces and enhances installation and removal.

Steering

Full hydraulic power steering provides automotive feel with positive, modulated flow control for constant steering response.

Service Points

Service points for the engine are grouped on the right-hand-side for easy access.

Floor Rollers

Sealed floor rollers eliminate lubrication.

Electro-Hydraulic Control

Simplifies serviceability by removing the cab pilot valve and associated line from the cab, which provides increased cab space as well as reduces noise. The high efficiency electro-hydraulic pilot oil filter provides cleaner oil for the pilot system.

Wiring Harness

Incorporates color-coded and numbered circuits for quick identification and simplified troubleshooting.

Cantilever Wheels

Provide greater parts commonality and ease of serviceability to the wheels and brakes.

Electronic Monitoring System (EMS)

Monitors the machine status and provides real-time information to the operator including warnings of problems identified by the Electronic Control Modules.

Convenient Diagnostic Connections

Allow quick trouble-shooting using the Electronic Technician (ET) service tool.

Parts Availability

Most Cat parts are immediately available from any dealer. Cat dealers rely on our worldwide computer network to find parts instantly and minimize machine downtime. Many components are economically available as Caterpillar Remanufactured Products.

Machine Management Services

Cat dealers help manage your equipment investment with:
• Effective preventive maintenance programs.
• Diagnostic programs such as S•O•SSM (Scheduled Oil Sampling) and Technical Analysis.
• Information to make the most cost-effective repair option decisions.
• Customer meetings, and training for operators and mechanics.

Flexible Financing

Your dealer can arrange affordable financing for the entire Caterpillar product line. Talk to your dealer to learn how terms can be structured to meet your cash flow requirements.