631K Wheel Tractor-Scraper



Technical Specifications
Benefits and Features
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Quick loading, high travel speeds and the ability to load and dump on the run yield fast cycle times, allowing Cat Wheel Tractor-Scrapers to consistently deliver high productivity at the lowest cost per ton.

Tractor Engine
Flywheel Power - Tractor/Scraper 570 HP
Scraper Bowl
Scraper Capacity - Heaped 34 yd³
Top Speed - Loaded 34.7 mile/h
Front of Tractor to Front Axle 142.2 in
Axle to Vertical Hitch Pin 20 in
Wheel Base 346.8 in
Rear Axle - Rear of Machine 108 in
Ground Clearance - Tractor 26.1 in
Height - Overall Shipping 153.2 in
Height - Scraper Blade Maximum 20 in
Height - Top of Cab 147 in
Length - Maximum (Push-Pull) 655.1 in
Length - Overall Machine - Standard 597 in
Width - Inside of Bowl 134 in
Width - Outside Rear Tires 143.2 in
Width - Overall Machine 155 in
Width - Rear Tire Centers 96.9 in
Width - Tractor 137.8 in
180° Curb-to-Curb Turning Width 40.12 ft
Fuel Tank Refill Capacity - Scraper 231 gal (US)
Maximum Depth of Cut 17.7 in
Maximum Depth of Spread 21.1 in
Overall Shipping Height 12.75 ft
Overall Width 12.93 ft
Rated Load 37 200 kg (82,200 lb); 37.2 tonnes (41.1 tons)
Scraper Capacity - Heaped 34 yd³
Scraper Capacity - Struck 24 yd³
Tires - Scraper 37.25R35**E3
Tires - Tractor 37.25R35**E3
Top Speed - Loaded 34.7 mile/h
Width - Cut 11.5 ft
Emissions Cat C18 engine meets U.S. EPA Tier 4 Final/EU Stage IV emission standards.
Engine Model - Tractor Cat C18
Flywheel Power - Tractor 570 HP
Rated Engine RPM - Tractor 1900 r/min
Service Refill Capacities
Cooling System 19.8 gal (US)
Crankcase - Tractor 13.7 gal (US)
Diesel Exhaust Fluid (DEF) 8 gal (US)
Fuel Tank 231 gal (US)
Hydraulic System 37.5 gal (US)
Transmission System 29 gal (US)
Non Push-Pull
Operating Weight - Empty 102750 lb
Overall Length 49.34 ft
Operating Weight - Empty 106430 lb
Overall Length - With Bail Down 54.59 ft
Exterior Sound Level The exterior sound power level for the standard machine (ISO 6393) is 111.5 dB(A).
ROPS/FOPS ROPS/FOPS meet “ISO Standards.”
Safety Criteria Compliance Standards
Brakes ISO 3450:2011
Falling Object Protective Structure (FOPS) ISO 3449:2005 Level II
Reverse Alarm ISO 9533:2010
Rollover Protection Structure (ROPS) ISO 3471:2008 for up to 21 282 kg (46,919 lb)
Seat Belt SAE J386:FEB2006
Steering System ISO 5010:2007
Travel Speeds - Runout
Transmission Gear - Eighth 34.7 mile/h
Transmission Gear - Fifth 14.1 mile/h
Transmission Gear - First 3.4 mile/h
Transmission Gear - Fourth 10.5 mile/h
Transmission Gear - Reverse 6.2 mile/h
Transmission Gear - Second 6.2 mile/h
Transmission Gear - Seventh 25.7 mile/h
Transmission Gear - Sixth 19 mile/h
Transmission Gear - Third 7.7 mile/h
Implement Cycle Times
Apron Lower 3.8 s
Apron Raise 4 s
Bail Lower 2.1 s
Bail Raise 1.5 s
Bowl Lower 3.5 s
Bowl Raise 3.5 s
Ejector Extend 8.5 s
Ejector Retract 8.5 s


• Up to 12% improvement in productivity.
• Advanced productivity electronic control system (APECS) allows
the engine and transmission to communicate on a high level. This
communication allows the machine to better utilize the power and torque the engine is producing. The net result is moving more material.
• Use ground speed control to set the desired top speed and the machine will find the gear that works best for the engine and the transmission, providing a lower fuel burn.
• The machine speed limit feature replaces top gear selection,
allowing the machine to find the correct gear that works best for
the engine and transmission. Pulling the load in the correct gear, in
most cases, results in lower engine load factor and lower fuel burn.
• Auto-stall assists in quickly bringing the transmission to an
operating temperature at startup when the machine is working in a
cold climate region.
• Cat Payload Estimator for scrapers is an earthmoving solution for optimal payload and jobsite efficiency. Payload Estimator achieves on-the-go weighing by using bowl lift cylinder pressure during the loaded haul segment. Payload Estimator is optimized to be used with sequence assist, which provides increased productivity with less operator effort. Payload Estimator is an automatic feature when ordered with sequence assist.


• Reduce up to 14 individual operator commands per cycle with sequence assist (optional attachment).
• Steer with less effort using the newly designed high-pressure
steering system.
• Enjoy interior improvements and a more ergonomic work environment with a 21% larger cab than the G Series cab.
• Intuitive, ergonomic controls keep operators focused on their work.
• Maintain desired cab temperature with automatic temperature control.


• Get in and out of the cab easier with the new powered access ladder system (optional attachment).
• Enhance an operator’s awareness of site surroundings with the optional work area vision system (WAVS).
• Seat belt indicator provides visual and audible alerts when the seat
belt is not in use.
• Advanced cushion hitch allows the cushion hitch to prevent end stroke by having the ability to predict end stroke events and manage the rate of dampening, resulting in reduced hitch maintenance and improved operator ride in rough conditions.
• Easy ground level access to fuel, water, and engine oil.


• The spacious cab features easy, intuitive controls and excellent
visibility. The cab provides a comfortable working environment for
all-day operation.
• Cat advanced ride management (ARM) seat suspension reduces
end stroke movement of the load cylinder for a smoother ride.
• Engine overspeed protection will automatically engage with no
operator input when the machine is in eighth gear. The machine will assist in slowing the machine speed by canceling the throttle command and engaging the engine compression brake.

Standard Equipment:

  • Note
    • Standard and optional equipment may vary. Consult your Cat dealer for details.
  • Power Train – Tractor
    • Cat C18
    • Compression engine brake
    • Electric start, 24V
    • Air cleaner, dry type with precleaner
    • Fan, hydraulic
    • Ground level engine shutdown
    • Radiator, aluminum unit core, 9 fins per inch
    • Guard, crankcase
    • Starting aid, ether
    • Braking system:
      • Primary and secondary, wet disc, hydraulic
      • Parking, hydraulic-released, spring-applied
      • Throttle lock
    • Transmission:
      • 8-speed planetary power shift
      • ECPC control
      • APECS software
      • Programmable top gear selection
      • Transmission hold
      • Differential lock
      • Guard, power train
      • Standard tire spin reduction
      • Ground speed control
      • Machine speed limit
      • Differential lock protection
  • Power Train – Scraper
    • Braking system:
      • Primary and secondary, dry caliper, hydraulic actuated
  • Electrical – Tractor
    • Alternator, 150 Amp
    • Batteries (4), 12V, 1,000 CCA, maintenance free, high output
    • Electrical system, 24V
    • Lighting system:
      • Headlights, LED
      • Turn signals with hazard function, LED floodlights, (2) cutting edge (1) bowl, halogen side vision (2)
    • Starting/charging receptacle
  • Electrical – Scraper
    • Alarm, backup
    • Lighting system:
      • Brake lights, LED
      • Turn signals with hazard function, LED
  • Operator Environment – Tractor
    • HVAC system, heat, AC, defrost
    • Thermostat control of HVAC system
    • Coat hook
    • Lunchbox platform with holding strap
    • Diagnostic connection (2)
    • 12V power ports (2)
    • Differential lock (1)
    • Dome courtesy light
    • Horn, electric
    • T-Handle implement control
    • Mirror, rearview
    • Radio ready
    • ROPS/FOPS cab, pressurized
    • Keypad switches:
      • Throttle lock
      • Wipers/washers
      • Hazard lights
      • Retarding level select
      • Work lights on, off
      • Information mode on Messenger Display
    • Safety tab rocker switches
    • Seat belt, static two-piece
    • Seat, Cat Advanced Ride Management (ARM), Cat Comfort Series 3, rotates 30 degrees
    • Steering wheel, tilt, telescoping, padded
    • Windows, right side emergency egress
    • Windows, sliding
    • Windows, laminated, zipped in
    • Windshield wipers, front and rear windows, includes washers
    • Door lock
    • Messenger Display
    • Gauges, warnings include:
      • Coolant temperature
      • Engine oil temperature
      • Hydraulic oil temperature
      • Diesel Particulate Filter (DPF) temperature
      • Fuel level
      • Park brake
      • Implement lockout
      • Brake system
      • Regeneration required
      • Throttle lock
      • System voltage
      • Secondary steering
      • Bail down
      • Ejector auto
      • Differential lock
      • Apron float
      • Transmission hold
      • Cushion hitch
      • High beam lights
      • Action lamp
      • Engine speed, rpm
      • Gear selection
      • DEF fill levels
  • Fluids
    • Extended Life Coolant to –37° C (–34° F)
  • Other Standard Equipment – Tractor
    • Advanced cushion hitch
    • Accumulators (cushion hitch) with Canadian Registration Number (CRN)
    • Fast oil change
    • Fenders, non-metallic
    • Heater, engine coolant 120V
    • Rims (2)
    • Tow hooks, front
    • Vandalism locks
    • Heater, engine coolant 120V
    • Steering locks
  • Other Standard Equipment – Scraper
    • Bowl:
      • 18.3 m3 (24 yd3), struck
      • 26 m3 (34 yd3), heaped
    • Vandalism locks
    • Rims (2)
    • Hydraulic position sensing cylinders (bowl lift and apron)

Optional Equipment:

  • Note
    • Standard and optional equipment may vary. Consult your Cat dealer for details.
  • Steering Arrangements
    • Secondary Steering Arrangement
  • Integrated Technologies
    • Sequence Assist Arrangement with Payload Estimator
    • Load Assist
    • Cat Grade Control with Load Assist
    • Advanced Tire Spin Reduction
  • Other Attachments
    • Camera arrangement – Work Area Vision System (WAVS)
    • Cab beacon
    • Air horn
    • Air horn and beacon
    • Fender, scraper
    • Guard, overflow
    • Wiring group
    • Push Pull
  • Service Instructions
    • Film arrangement – U.S. (ANSI)
    • Film arrangement – International (ISO)

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