®®

EngineTractor Engine Cat® 3406E

Net Power 246/272 kW 330/365 hpScraper Engine Cat C-9

Net Power 168/186 kW 225/250 hpHeaped Capacity 17 m3 22 yd3

Rated Load 23 950 kg 52,800 lb

621G/627GWheel TractorScrapers

2

621G/627G Wheel Tractor ScrapersResponsible, productive earthmoving machines, built to last.

Quick loading, high travel speeds and theability to load and dump on the run yieldfast cycle times, allowing Caterpillar WheelTractor-Scrapers to consistently deliver highproductivity at the lowest cost per ton.

Auger Arrangement

Provides self-loading capability withthe same wide material appetite as anopen bowl machine. pg. 13

Push-Pull Arrangement (627G only)

For maximum production capability,Caterpillar offers an optional push-pullarrangement for the 627G, which allowstwo push-pull scrapers to act as a self-loading machine. pg. 12

Electronic Controls

The electronic controls respond tooperator commands and input from on-board sensors to optimize machineperformance. In addition, the electroniccontrols provide advanced diagnosticcapabilities that result in better machineavailability. pg. 7

Power Train - Transmission

Caterpillar planetary powershifttransmission design offers greaterload carrying capacity than competitivedesigns by providing a larger contactarea between gears. Individual clutchmodulation provides fast, smooth shiftsand improved serviceability. pg. 6

Power Train - Engine

Electronically controlled Caterpillar®

engines and automatic planetarypowershift transmissions areelectronically integrated to providemaximum power to the cutting edgeand exceptional haul road speed. pg. 4

✔

✔ New Feature

3

Customer Support

The best parts availability and the bestservice capability will help keep yourequipment working. pg. 15

Serviceability

Grouped service points, the latestelectronic monitoring systems andrugged Caterpillar components simplifymaintenance and minimize downtime.pg. 14

✔

Scraper Bowl

Caterpillar Scraper bowls are designedfor excellent material flow for fast cycletimes and high productivity. pg. 11

✔

Structures

Superior structural design delivers state-of-the-art ride, capacity, and materialcontrol while assuring the durabilityand reliability customers expect fromCaterpillar. pg. 10

Operator Station

The all-new interior incorporatesconvenient control placement and acomfortable work environment, keysto high productivity. Features includeelectro-hydraulic controls, a new airseat suspension and improvedinstrumentation. pg. 8

✔

3406E Tractor Engine. The 3406E, withdual horsepower capability, provideshigh power and torque rise for excellentlugging in tough loading conditions.The 3406E is designed for long hoursof continuous operation with highdisplacement and low RPM ratings.

C-9 Scraper Engine. The 627G istandem powered by the C-9 scraperengine for peak performance and highproductivity in self-loading applications.

Dual Horsepower. The electronicengines of the tractor and scraperprovide increased power when theauger is engaged or when the machineis in the roading gears, which providesquicker acceleration on the haul road.

Emissions Compliant. The 3406Eand the C-9 engines are U.S.Environmental Protection AgencyTier 2 and EU Stage II compliant.

HEUI™ Fuel System. Hydraulicallyactuated, electronically controlled unitinjectors deliver fuel precisely for clean,efficient combustion and excellent fueleconomy. The HEUI system has fewermoving parts than mechanical unitinjection, for greater reliability andlower maintenance costs.

Electronic Control Module. The ECMresponds to operator commands andengine sensor input to optimize engineand machine performance. This advancedengine management software controls andprotects the engine at all times againstcold starts, high altitude operations andair filter plugging by monitoring:

• injection timing and pressure

• engine cooling fan speed

• ether starting aid

• hydraulic pumps

Advanced Diesel Engine Management.Controls engine rpm by adjusting thefuel duration, which results in quickerstarts in hot and cold weather, betterfuel economy, better operator response,and automatic compensation for altitudeand filter plugging.

4

Proven components are electronically integrated to achieve new levels of performanceand efficiency.

Power Train - Engine

Greater Reliability. The HydraulicElectronic Unit Injection system is morereliable because it has fewer movingparts than mechanical unit injectionand requires very few adjustments.

Maintenance. HEUI engines havevirtually no mechanically controlledparts to wear or adjust.

Electronic Control Throttle Shifting(CTS). Automatically synchronizesengine speed to transmission speedduring shifting to reduce power trainstress and increase component life.

Ether Starting Aid. ECM activatesthe ether injection system duringengine cranking to help ensurereliable engine start-up in extremecold operating conditions.

Directional Shift Management. Regulatesengine speed to prevent damage causedby high-speed directional changes.

Altitude Compensation. ECM matchesatmospheric pressure with elevationproviding full engine power up to3350 m (11,000 ft). Above thatelevation, it automatically deratesengine to maintain proper fuel-to-airmixture for clean, efficient combustion.

Diagnostic Capability. ElectronicTechnician (Cat ET) is used to displayreal-time pressures, temperatures, fuelsettings and diagnostic messages aswell as a historical information such asengine over-speeds, overheating, low oilpressure and air filter restriction events.

Fuel Economy. Electronic controlsare expected to yield a fuel savingsby optimizing the timing settingfor varying conditions.

Air Filter Restriction. The ECM monitorsair filter restriction and sends a warningmessage to the Electronic MonitoringSystem III to alert the operator if therestriction exceeds the allowable limit.

Reduced Exhaust Smoke. The ECMdetermines the optimum fuel/air ratio,then precisely controls fuel duringcranking, starting and acceleration toreduce smoke. This system is fasterand more efficient than mechanicallycontrolling the governor rack position.

Tractor Radiator. The radiators on boththe tractor and the scraper pull the airfrom grill side across the radiator finsfor cooling. The folded core radiator iscomprised of individual modules set ina V configuration with 33 fins per inch.The modular design simplifies servicing,and using a V configuration maximizessurface area in a compact design.

Scraper Radiator. The standard radiatoron the scraper is a one-piece unit designwith 9 fins per inch, eliminating theneed for an attachment radiator.

5

Transmission. Electronically controlledCaterpillar planetary powershifttransmission with eight forward andone reverse speed. Tractor gears 1 & 2operate in converter drive for increasedtorque capability during cut and filloperations. Gears 3-8 operate in direct-drive for drive train efficiency duringthe haul. All scraper gears operate inconverter drive for increased torquecapability during the cut and fill.

Planetary Design. Provides largercontact area between gears thancountershaft transmissions for greaterload-carrying capacity.

Transmission Hold. Allows the operatorto maintain converter drive for increasedrimpull, or hold the current gear forenhanced control.

Programmable Top Gear Selection.Allows the operator to manually set thetop gear (3rd - 8th) available to matchconditions or to match the hauling speedof the fleet to specific job-site needs.

Retarder. The retarder can be used toslow the ground speed of the machinewhen entering the cut or fill area toallow the transmission to downshift.

Differential Control. Electronicdifferential lock helps prevent the drivewheels from spinning in poor underfootconditions. The operator engages thedifferential lock with a foot controllocated in the cab.

Clutch Modulation. Individual clutchmodulation provides fast, smooth shiftsand improved serviceability.

Neutral Coast Inhibitor. Neutral coastinhibitor prevents the transmission fromshifting into neutral if the operator selectsneutral while moving.

Final Drives. Outboard-mounted,planetary design final drives reducetorque loads on other power traincomponents. Large-capacity, double-rowroller bearings and Caterpillar Duo-Coneseals deliver exceptional reliability inthe toughest applications.

Brake Performance. Redesignedaxles on both the tractor and scraperaccommodate wider brake shoesand brake drums, improving brakeperformance as much as 20 percentand reducing brake and drum wearas much as 75 percent.

Independent Systems. Expanding shoe-type brakes are a cam-operated designthat is air-applied and spring released.The braking system uses independentfront and rear circuits with secondarybrakes automatically applied if theservice air pressure drops to 380 kPa(55 psi).

Parking Brakes. The push-buttonoperated parking brake features aspring-applied, air-released mechanismthat operates the service brakes.

6

Power Train - TransmissionIntegrated electronics allows the machine to monitor the power train which reduces stressas well as provide a better ride to the operator.

Simplified System. The electrical systemhas been redesigned to utilize threeelectronic control modules (ECM) onthe tractor instead of four. The rear-powered scraper now has two ECMsrather than three.

Air Filter Restrictor Indicator. Electroniccontrol module monitors air filterrestriction and sends a warning messageto the electronic monitoring system toalert the operator if the restriction exceedsthe allowable limit.

Automatic Ether Injection. The ECMactivates the ether injection systemduring engine cranking to enhancecold weather starting.

Automatic Altitude Compensation. Athigh altitudes the system automaticallyde-rates fuel delivery as a functionof barometric pressure sensed by thesystem’s atmospheric pressure sensor.

Low Battery Elevated Idle. The ECMautomatically compensates for lowalternator output at low idle to keepthe batteries fully charged.

Improved Serviceability. Combinedmonitoring systems, easy accessdiagnostics and more durable componentsmake routine maintenance and servicingsimple and fast.

Combined EMS Monitoring.The Electronic Monitoring System(EMS III) is designed to monitorboth the tractor and scraper fromone location instead of two. Both thetractor and powered scraper use thesame controller for parts commonalityand easier servicing.

Easy Access Diagnostics. Real-timepressures, temperatures, fuel settingsand diagnostic messages and historicalinformation such as engine over-speeds,overheating, low oil pressure, andair filter restriction events can beaccessed via the Caterpillar ElectronicTechnician (Cat ET) Service Tool foreasy diagnostics.

Greater Reliability. Caterpillar’s HEUIfuel system uses hydraulic electronicunit injectors, has fewer moving partsthan mechanical unit injection, andrequires few adjustments.

Maintenance. With fewer mechanicallycontrolled parts to wear or adjust, theelectronic controls reduce maintenancecosts and increase machine availability.

Fuel Economy. Electronic controls yielda fuel savings by optimizing the timingsetting for varying conditions.

Product Link Ready. Mounting locationsand wiring provided for Product Link,which allows customer to track machinelocation, hours, and machine health. Thesystem has the capability to automaticallyissue alerts when the machine is beingoperated beyond owner defined timeand location limits.

Reduced Exhaust Smoke. Utilizingelectronic sensors, the optimum air/fuelratio is precisely controlled by the ECMduring all segments of the haul cycle.This results in a reduction of smoke andparticulates during cranking, starting,and acceleration.

7

Electronic ControlsInstant response optimizes machine performance, and advanced diagnostic capabilitiesmaximize machine availability.

Multi-Adjustable Seat. The CatComfort Cloth Seat has an adjustableseat and armrests for maximum operatorcomfort.

• Swivels and locks in four positions(0º to 30º) providing the optimumoperating position in the cut or onthe haul.

• Fore/aft and vertical heightadjustment to accommodatevarious sized operators.

Seat Suspension. The new standardseat suspension redefines the ride ofscrapers. It features a self-containedair compressor with a high performanceair shock absorber.

Revised Steering Column. Increasesleg room a full 89 mm (3.5 in), andreduces knee contact.

Standard Air Conditioning. Standardair conditioning system with improvedventilation location enhances airflow inthe cab.

Storage And Amenities. Convenientstorage location includes space for alunch box and first aid kit. The cab alsohas a cup holder as well as an ashtray.

8

Redesigned for enhanced operator comfort and productivity.

Operator Station

Visibility. The redesigned hood hassloped corners to maintain visibility.The exhaust is located at the back of thehood for good visibility to the right side.

Single Lever Implement Control.Simple and easy to operate, the joystickenhances the productivity of operatorsof all skill levels. Requires less force tocontrol the critical scraper functionsand requires less lever travel.

1) Bowl (forward & back)

2) Ejector (side to side)

3) Apron (thumb rocker switch)

4) Transmission Hold

5) Cushion Hitch

6) Trigger (not shown - is on front ofjoystick)

• Auger (on/off)

• Push-Pull (bail up/down)

* Standard open bowl does not havea trigger.

Simplified Transmission Control.Simplifies gear selection (1st, 2nd,Drive and Reverse) and allowsoperator-defined top gear control.Relocating the gear control to therear increases operator legroom.

Instrument Display Panel. Featuresa new quad-gauge layout showingengine coolant temp, transmission/torque converter oil temp, fuel level,and system air pressure. The 627Gtachometer can monitor either frontor rear engine speeds. Once the 627Gtractor engine has been started, theoperator can start the rear engine frominside the cab using a switch on theinstrument panel. EMS III can displayboth front and rear engine informationright in the cab.

Throttle Lock Controller. Enhancesoperation during long haul cyclesby allowing the operator to maintaina desired engine speed withoutmaintaining pressure on the throttle.

9

14

5

3

(Down)

1 (Up)

2 (Forward) 2 (Return)

Cushion Hitch. The electronicallyactuated cushion hitch incorporatesa parallelogram-type linkage forexceptional strength with nitrogenaccumulators to deliver a smoothride for enhanced operator comfort.

• controlled oil flow dampens reboundoscillation

• leveling valve automatically centerspiston in cylinder for all loads

• steel castings are used extensivelyto eliminate many welded joints andincrease strength

• double-kingbolt design withstandshigh external forces and simplifiesinstallation and removal

Nitrogen Accumulators. Verticallymounted hydraulic cylinder transfersroad shocks to nitrogen accumulators.Nitrogen accumulators absorb anddampen road shocks, thus preventingthese loads from being transmitted tothe operator.

Lockout Switch. An operator-selectablelockout switch, located on the joystick,locks the cushion hitch for improvedcontrol of the cutting edge duringloading and dumping.

10

StructuresSuperior structural design and construction optimize performance and reliability.

1 Load cylinder2 Hitch castings3 Scraper gooseneck4 Nitrogen accumulators5 Orifice6 Oil from tractor hydraulic system7 Leveling valve8 Free floating pistons

1

2

3

4

8

4

8

5

6

7

Redesigned Bowl. Excellent productivitywith a 10% increase in bowl capacity,improved draft arm protection, andbetter load retention. Low-profiledesign of the bowl offers less resistanceto incoming materials, while cellularconstruction adds strength and dentresistance to bowl sides and floor.

Bulldozer Ejection System. Combinesconstant spreading control whileminimizing carryback material. A spillguard on the ejector helps retain materialand keep it from spilling over onto therear of the scraper.

Cutting Edges. May be adjusted accordingto job conditions. The stinger (drop down)position provides good penetration andefficient flow of material into the bowlwhereas the level cutting edge is usedfor finish work or very high impactconditions.

Caterpillar Ground Engaging Tools(G.E.T.). A wide variety of GroundEngaging Tool (GET) options, such asstandard, serrated, and abrasion resistantmaterial (ARM), are available to optimizescraper loading in various materials.Most are reversible to provide long lifeand reduced operating costs. Contactyour Cat Dealer to learn more aboutthe best tools for your applications.

Tandem Engine. Two engines ensurethe power to handle steep grades, andmakes possible all wheel drive to handlesoft, slippery underfoot conditions.

Dual Horsepower. Provides increasedhorsepower during the haul whichresults in faster cycle times.

Material Application. Well suited tohandle a wide variety of material fromclay to shot rock.

Push-Loading. To achieve maximumproductivity, the 621G should bepush loaded by a D9R or D10R Track-Type Tractor.

11

Scraper BowlDesigned for optimum loading, material retention and ejection.

Push-Pull Attachment. This optionalarrangement concentrates the combinedhorsepower of two machines onto onecutting edge. The push-pull attachmentallows two individual machines to actas a self-loading system, typically loadingboth machines in less than a minute.

Flexible Fleet. This system providesa more balanced, flexible fleet usingfewer machines and less investmentthan comparable self-loading or push-loading systems.

Hydraulically Actuated Bail. The push-pull arrangement uses a hydraulicallyactuated bail and cushioned plate boltedto the front of the tractor, and a hook thatis attached to the rear of the scraper.

12

Push-Pull Arrangement (627G only)Caterpillar offers a self-loading arrangement for the 627G.

Versatility. The auger has a widematerial appetite ranging from rockto free flowing material such as sand.The auger lifts material off of thecutting edge, conditions it, andspreads it evenly in the bowl.

Auger Mechanism. The auger liftsmaterial off of the cutting edge andcarries it to the top of the load fortrue self-loading capability.

Material Handling. The auger actionson the material produce several benefits:

• wide material appetite, ideal forlandfills

• blends the material to help eliminatevoids in the bowl for consistentpayloads

• conditions material which promotescompaction in the fill

• reduces dust and noise during loading

• precise metering of material in the fill

Dual Horsepower. Tractor engineautomatically reverts to the highersetting when the auger motoris engaged.

Slip Limiter Switch. Prevents rearwheel slip during loading.

Hydraulic System. Single hydraulicsystem for entire machine with separateimplement pumps/valves simplifiesmaintenance and improves reliability.

Electro-hydraulic Controls. The 627Gfeatures full electro-hydraulic controls,which improve serviceability and reducenoise by replacing the cab pilot valveswith a single-lever joystick control.

Full-flow Circuits. The hydraulic systemfeatures closed-loop, full-flow hydrauliccircuits powered by vane-type andpiston-type pumps.

Apron. Prevents material spillage andretains fine material far better than anelevating scraper.

13

Auger ArrangementExcellent self-loading capability in a wide range of material.

Grouped Service Points. Maintenanceand service points for the engine aregrouped on the right-hand side foreasy access. They include the engineair cleaner, engine oil check and fill,fuel filters and priming, coolant levelsight glass, window washer bottle,air conditioning dryer cartridge, etherstarting aid canister, engine oil filter,fan drive lubrication, and samplingports for the engine oil and coolant.

• Spin-on fluid filters for all but themain hydraulic filter

• Cab wiring harness redesigned andrelocated for better serviceability

Electronic Monitoring System (EMS III).Monitors machine status and providesreal-time information to the operatorincluding warnings of problems identifiedby the Electronic Control Modules.

Electro-Hydraulic Implement Control.Simplifies serviceability by removingthe cab pilot valve and associatedlines, which also improves reliabilityand reduces noise. The high efficiencyelectro-hydraulic pilot oil filter providescleaner oil for the pilot system.

Electronic Technician (Cat ET).The Caterpillar Electronic Technician(Cat ET) Service Tool is useful introubleshooting existing problemsor identifying potential problemsby displaying:

• Real-time pressures, temperatures,fuel settings and diagnostic messages

• Historical data such as engine over-speeds, overheating, low oil pressureand air filter restriction events

• More detailed information to theservice technician who can accessCat ET via a laptop computer

Easy Access Diagnostics. Diagnosticcodes are accessible through the EMSmain display module, via the Cat ET.Relaying this information to the servicetechnician can let him know whichtools, troubleshooting guides, andpossibly even replacement parts tobring to the machine.

14

ServiceabilityCount on Caterpillar for simplified service and the most productive uptime.

Product Support. You will find nearlyall parts at our dealer parts counter.Cat dealers use a world-wide computernetwork to find in-stock parts to minimizemachine down time. Save money withgenuine Cat Reman parts. You receivethe same warranty and reliability as newproducts at substantial cost savings.

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

Purchase. Look past initial price.Consider the financing options availableas well as day-to-day operating costs.Look at dealer services that can beincluded 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.

Operation. Improving operatingtechniques can boost your profits.Your Cat dealer has videotapes,literature and other ideas to help youincrease productivity, and Caterpillaroffers certified operator training classesto help maximize the return on yourmachine investment.

Maintenance Services. Talk to yourdealer about the range of availablemaintenance services. Repair optionprograms guarantee the cost of repairsup front. Diagnostic programs such asS•O•SSM Analysis and Coolant Samplingand Technical Analysis help avoidunscheduled repairs.

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

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Customer SupportCat dealer services help you operate longer with lower costs.

16 621G/627G Wheel Tractor Scrapers specifications

Transmission

1 Forward 5 kph 3.1 mph2 Forward 7.6 kph 4.7 mph3 Forward 10.9 kph 6.8 mph4 Forward 14.8 kph 9.2 mph5 Forward 19.9 kph 12.4 mph6 Forward 26.9 kph 16.7 mph7 Forward 36.4 kph 22.6 mph8 Forward 51.5 kph 32 mphReverse 8.9 kph 5.4 mph

Steering

Width Required for 10.9 m 35.9 ftCurb-to-Curb 180° TurnSteering Angle - Right 90°Steering Angle - Left 85°Hydraulic Output 209 L/min 55 gal/min

• Optional supplemental steering system meets SAE J1511(OCT 90) and ISO 5010 (1992) requirements.

• Steering circuit at 1900 RPM

Standards

• Rollover Protective Structure (ROPS) meets SAE J320a,SAE J1040 MAY 94, ISO 3471-1986 and ISO 3471-1994

• Falling Object Protective Structure (FOPS) meetsSAE J231 JAN 81 and ISO 3449-1992

• The operator sound exposure Leq (equivalent sound pressurelevel) measured according to the work cycle proceduresspecified in ANSI/SAE J1166 OCT98 is 80.5 dB(A), for caboffered by Caterpillar, when properly installed and maintainedand tested with the doors and windows closed.

• Hearing protection may be needed when operating with anopen operator station and cab (when not properly maintainedor doors/windows open) for extended periods or in noisyenvironments.

Engine

Tractor Engine Cat 3406EScraper Engine Cat C-9

Tractor Engine

Net Power - Gears 1-2 246 kW 330 hpNet Power - Gears 3-8 272 kW 365 hpGross Power - Gears 1-2 267 kW 358 hpGross Power - Gears 3-8 293 kW 393 hpBore 137 mm 5.4 inStroke 165 mm 6.5 inDisplacement 14.6 L 893 in3

• Net power advertised is the power available at rated speedof 1800 rpm, measured at the flywheel when the engine isequipped with fan, air cleaner, muffler and alternator.

Scraper Engine

Net Power - Gear 1 168 kW 225 hpNet Power - Gears 2-4 185 kW 249 hpGross Power - Gear 1 168 kW 225 hpGross Power - Gears 2-4 186 kW 249 hpBore 112 mm 4.41 inStroke 149 mm 5.87 inDisplacement 8.8 L 538 in3

• Net power advertised is the power available at rated speedof 2200 rpm, measured at the flywheel when the engine isequipped with fan, air cleaner, muffler and alternator.

Scraper Bowl

Heaped Capacity 17 m3 22 yd3

Rated Load 23 950 kg 52,800 lbStruck Capacity 12 m3 15.7 yd3

Maximum Depth of Cut 333 mm 13.1 inWidth of Cut, Outside Router Bits 3023 mm 9.11 ftMaximum Ground Clearance 553 mm 21.7 inThickness of Optional Cutting Edge 29 mm 1.14 inMaximum Hydraulic Penetration Force

- 627G 215 kN 48,375 lb- 621G 150 kN 33,721 lb

Maximum Depth of Spread 522 mm 20.6 inApron Opening 1780 mm 70 inApron Closure Force 107 kN 24,075 lb

17621G/627G Wheel Tractor Scrapers specifications

DimensionsAll dimensions are approximate.

Dimension/Model 621G 627G1 Overall machine width 3467 mm 11'5" 3467 mm 11'5"

2 Cab width 3130 mm 10'4" 3130 mm 10'4"

3 Width to center of rear tires 2200 mm 7'3" 2200 mm 7'3"

4 Width to inside of bowl 2946 mm 9'8" 2946 mm 9'8"

5 Width to outside of tires 3048 mm 10'0" 3048 mm 10'0"

6 Overall shipping height 3705 mm 12'2" 3705 mm 12'2"

7 Height to top of cab 3423 mm 11'3" 3423 mm 11'3"

8 Tractor ground clearance 553 mm 1'10" 553 mm 1'10"

9 Length to front of machine from front axle 3058 mm 10'1" 3058 mm 10'1"

10 Width from center of rim to outside of rim 432 mm 1'6" 432 mm 1'6"

11 Maximum scraper blade height 522 mm 1'9" 522 mm 1'9"

12 Wheelbase 7722 mm 25'5" 7722 mm 25'5"

13 Overall machine length 12 917 mm 42'5" 12 917 mm 42'5"

14 Length to rear of machine from rear axle 2142 mm 7'1" 2142 mm 7'1"

15 Maximum bail length for push-pull — — 1612 mm 5'4"

16 Extended push block — — 2786 mm 9'2"

21 53 76

9

11

12 14

13

8

104

621G

12 3 4 5 6

7

15 9 1 2

10

14

8

13

11

16627G

18 621G/627G Wheel Tractor Scrapers specifications

HydraulicsClosed, full-flow filtered hydraulic circuits powered by vane-type and piston-type pumps.

Model 621G 627GDouble acting bowl cylinders (2)

Dimensions: bore 152 mm 6 in 152 mm 6 in

stroke 813 mm 32 in 813 mm 32 in

Double acting apron cylinder (1)

Dimensions: bore 184 mm 7.25 in 184 mm 7.25 in

stroke 597 mm 23.5 in 597 mm 23.5 in

Double acting ejector cylinder (1)

Dimensions: bore 165 mm 6.5 in 165 mm 6.5 in

stroke 1549 mm 61 in 1549 mm 61 in

Steering circuit at 1900 rpm 209 liter/min 55 gal/min 209 liter/min 55 gal/min

Scraper circuit at 1900 rpm 284 liter/min 65.5 gal/min 284 liter/min 65.5 gal/min

Cushion hitch circuit at 1900 rpm 37 liter/min 9.8 gal/min 37 liter/min 9.8 gal/min

Optional supplemental steering circuitat 24 km/h (14.9 mph) 150 liter/min 39.9 gal/min 150 liter/min 39.9 gal/min

Relief valve settings for:

Steering circuit 15 500 kPa 2250 psi 15 500 kPa 2250 psi

Implement circuit 15 000 kPa 2175 psi 15 000 kPa 2175 psi

Service Refill Capacities

Model 621G* 627G* Tractor 627G ScraperL gal L gal L gal

Fuel tank 606 160 — — 1105 292

Crankcase 36 9.5 36 9.5 30 7

Transmission 72 19 72 19 59 15.6

Differential 144 38 144 38 15 4

Final drive, each side 19 5 19 5 19 5

Cooling system 107 28 107 28 77 20.3

Hydraulic 140 37 140 37 — —

Wheel coolant, each 45 12 45 12 45 12

Windshield washer 6 1.5 6 1.5 — —

19621G/627G Wheel Tractor Scrapers specifications

Model 621G 627G 627GStandard Push-Pull

Shipping, with ROPS cab and 10% fuelTractor 69% 59% 61%

22 052 kg 48,616 lb 22 151 kg 48,836 lb 23 534 kg 51,885 lb

Scraper 31% 41% 39%

9906 kg 21,841 lb 15 393 kg 33,937 lb 15 047 kg 33,172 lb

Total 100% 31 958 kg 70,458 lb 37 545 kg 82,773 lb 38 581 kg 85,058 lbOperating empty, with ROPS cab, full fuel tanks and operator

Front axle 68% 59% 60%

22 143 kg 48,817 lb 22 508 kg 49,622 lb 23 512 kg 51,834 lb

Rear axle 31% 41% 40%

10 420 kg 22,973 lb 15 641 kg 34,483 lb 15 674 kg 34,556 lb

Total 100% 32 563 kg 71,790 lb 38 149 kg 84,105 lb 39 186 kg 86,390 lbLoaded, based on a rated load of: 23 950 kg 52,800 lb 23 950 kg 52,800 lb 23 950 kg 52,800 lb

Front axle 53% 48% 49%

29 952 kg 66,033 lb 29 808 kg 65,714 lb 30 936 kg 68,203 lb

Rear axle 47% 52% 51%

26 561 kg 58,557 lb 32 291 kg 71,191 lb 32 199 kg 70,987 lb

Total 100% 56 513 kg 124,590 lb 62 099 kg 136,905 lb 63 135 kg 139,190 lb

Weights (approximate)

20 621G/627G Wheel Tractor Scrapers specifications

Gradeability/Speed/Rimpull

To determine gradeability performance: Read from grossweight down to the percent of total resistance. Total resistanceequals actual percent grade plus 1% for each 9 kg/t (20 lb/ton)of rolling resistance. From this weight-resistance point, readhorizontally to the curve with the highest obtainable gear, thendown to maximum speed. Usable rimpull will depend upontraction available and weight on drive wheels.

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70

0.6

0.8

1

2

4

6

8

10

20

40

60

80

100

10 20 40 60 80 100 200

km/h

mph

kg x 1000

lb x 1000lb x1000

kg x1000

30%25%

20%

15%

10%

8%

6%

4%

2%

0 5 10 15 20 25 30 35 40

1

2

4

6

8

10

20

40

60

80

100

200

4 6 8 10 20 40 60 80 100

Direct Drive

Torque Converter Drive

621G Gross Weight33.25 R29 Tires

Speed

Tota

l Res

ista

nce

(Gra

de p

lus

Rolli

ng R

esis

tanc

e)

Rim

pull

1—1st Gear Torque Converter Drive2—2nd Gear Torque Converter Drive3—3rd Gear Direct Drive4—4th Gear Direct Drive5—5th Gear Direct Drive6—6th Gear Direct Drive7—7th Gear Direct Drive8—8th Gear Direct Drive

E—Empty 32 563 kg (71,790 lb)

L—Loaded 56 513 kg (124,590 lb)

3rd Gear

1st Gear

2nd Gear

4th Gear

5th Gear6th Gear

7th Gear8th Gear

E L

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 km/h

mph

kg x 1000

lb x 1000

1%

25%

5%

10%

15%

20%

0 10 20 30 40 50 60 70 80

0 20 40 60 80 100 120 140 160 180

0 5 10 15 20 25 30

Retarding

To determine retarding performance: Read from gross weightdown to the percent effective grade. (Effective grade equalsactual percent grade minus 1% for each 9 kg/t (20 lb/ton) ofrolling resistance). From this weight-effective grade point,read horizontally to the curve with the highest obtainablespeed range, then down to maximum descent speed theretarder can properly handle.

621G RetardingGross Weight

Speed

Effe

ctiv

e G

rade

(Fav

orab

le)

3—3rd Gear Direct Drive4—4th Gear Direct Drive5—5th Gear Direct Drive6—6th Gear Direct Drive7—7th Gear Direct Drive8—8th Gear Direct Drive

E—Empty 32 563 kg (71,790 lb)

L—Loaded 56 513 kg (124,590 lb)

3rd Gear

4th Gear

5th Gear

6th Gear7th Gear

8th Gear

E L

21621G/627G Wheel Tractor Scrapers specifications

Retarding

To determine retarding performance: Read from gross weightdown to the percent effective grade. (Effective grade equalsactual percent grade minus 1% for each 9 kg/t (20 lb/ton) ofrolling resistance). From this weight-effective grade point,read horizontally to the curve with the highest obtainablespeed range, then down to maximum descent speed theretarder can properly handle.

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 km/h

mph

kg x 1000

lb x 1000

1%

25%

5%

10%

15%

20%

30%

0 10 20 30 40 50 60 70 80

0 20 40 60 80 100 120 140 160 180

0 5 10 15 20 25 30

627G RetardingGross Weight

Speed

Effe

ctiv

e G

rade

(Fav

orab

le)

3—3rd Gear Direct Drive4—4th Gear Direct Drive5—5th Gear Direct Drive6—6th Gear Direct Drive7—7th Gear Direct Drive8—8th Gear Direct Drive

E—Empty 38 149 kg (84,105 lb)

L—Loaded 62 099 kg (136,905 lb)

3rd Gear

4th Gear

5th Gear

6th Gear

7th Gear8th Gear

E L

Gradeability/Speed/Rimpull

To determine gradeability performance: Read from grossweight down to the percent of total resistance. Total resistanceequals actual percent grade plus 1% for each 9 kg/t (20 lb/ton)of rolling resistance. From this weight-resistance point, readhorizontally to the curve with the highest obtainable gear, thendown to maximum speed. Usable rimpull will depend upontraction available and weight on drive wheels.

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70

0.6

0.8

1

2

4

6

8

10

20

40

60

80

100

10 20 40 60 80 100 200

km/h

mph

kg x 1000

lb x 1000lb x1000

kg x1000

30%25%

20%

15%

10%

8%

6%

4%

2%

0 5 10 15 20 25 30 35 40

1

2

4

6

8

10

20

40

60

80

100

200

4 6 8 10 20 40 60 80 100

Direct Drive

Torque Converter Drive

627G Gross Weight33.25 R29 Tires

Speed

Tota

l Res

ista

nce

(Gra

de p

lus

Rolli

ng R

esis

tanc

e)

Rim

pull

1—1st Gear Torque Converter Drive2—2nd Gear Torque Converter Drive3—3rd Gear Direct Drive4—4th Gear Direct Drive5—5th Gear Direct Drive6—6th Gear Direct Drive7—7th Gear Direct Drive8—8th Gear Direct Drive

E—Empty 38 149 kg (84,105 lb)

L—Loaded 62 099 kg (136,905 lb)

3rd Gear

1st Gear

2nd Gear

4th Gear5th Gear

6th Gear7th Gear

8th Gear

E L

22 621G/627G Wheel Tractor Scrapers specifications

Standard Equipment

POWER TRAINEngine

Electric start, 24VFan, suctionGround level engine shutdownMufflerStarting Aid, etherThermo-shield, laminatedTractor:

6 cylinder diesel, 3406E HEUIAir Cleaner, dry-type with pre-cleanerGuard, crankcase

Scraper (627G):6 cylinder diesel, C-9 Diesel HEUIAlternator, 35 amp

Braking SystemParking/Primary/SecondaryShields- brake

TransmissionTractor:

8-speed automatic Powershift with Electronic ControlControl throttle shiftingDifferential - lockupDownshift InhibitorNeutral Coast InhibitorProgrammable top-gear selection

Scraper (627G):4-speed Powershift, Electronic Control

OTHER STANDARD EQUIPMENTFast Oil ChangeFendersExtended Life Coolant, –36°C (–33°F)Tires/Rims - 33.25-R29 radialTractor:

Air dryerCushion hitchLocks, vandalism protectionProduct Link readyTow Pins - front and rear

ELECTRICALAlarm, backupAlternator, 75 amp - tractor engineAlternator, 35 amp - scraper engine (627G)Batteries (4), 12V Maintenance Free, High Output Batteries (2), 12V Maintenance Free, High Output (627G)Electrical System, 24V Lighting System - Tractor

Directional Signals; Hazard Lights; Headlights, halogenwith dimmer; Floodlight, cutting edge

Lighting System - ScraperDirectional Signals; Hazard Lights; Stop/Tail

Starting Receptacle - tractor and scraper engines

OPERATOR ENVIRONMENTAir Conditioner (includes heater and defroster)Cigarette Lighter and AshtrayCoat HookDiagnostic Connection Port (12V)Dome Courtesy LightGauge Group

Air PressureConverter/Retarder temperatureElectronic Monitoring System (EMS III)Engine coolant temperatureActual Transmission Gear IndicatorFuelSpeedometerTachometerTransmission gear indicator

HornImplement Control JoystickRearview MirrorsRadio Ready (two bays, speakers, 5-amp converter)ROPS Cab with Sound Suppression and PressurizationStatic SeatbeltScraper Engine Controls (627G)Seat, Air Suspension, Caterpillar Comfort, clothSteering Wheel - tilt and telescopingStorage CompartmentThrottle LockTransmission HoldWindows - sliding side, swingoutWindshield - laminated glassWindshield Wiper/Washer - front and rear

23621G/627G Wheel Tractor Scrapers specifications

Optional EquipmentOptional equipment may vary. Consult your dealer for specifics.

kg lb627G

Auger 4536 10,000Fuel system, fast-fill 10 23Heater, engine coolant 2 4Lights, side vision 5 10Push block, extended (scraper) 200 440Push-pull arrangement (scraper) 489 1078Push-pull arrangement (scraper)

w/o rear engine radiator guard 349 770Retarder, hydraulic (tractor) 150 330Retarder, hydraulic (scraper) 154 340Steering, secondary 50 110

kg lb621G

Auger 4536 10,000Fenders, scraper 121 266Fuel system, fast-fill 10 23Heater, engine coolant 2 4Lights, side vision 5 10Retarder, hydraulic 150 330Steering, secondary 50 110

R

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

© 2003 CaterpillarPrinted 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.

AEHQ5528 (1-03)

Replaces AEHQ5412 (10-00)

621G/627G Wheel Tractor Scrapers