988K XE Wheel Loader



Technical Specifications
Benefits and Features

Cat® Large Wheel Loaders are designed with durability built in, ensuring maximum availability through multiple life cycles. With optimized performance and simplified serviceability, our machines allow you to move more material efficiently and safely at a lower cost per ton.
Introduced in 1963, the 988 has been the industry leader for over 50 years, built on a legacy of reliability, performance, safety, operator comfort, serviceability, and productivity. The 988K XE brings improved sustainability and maximum efficiency to this machine platform.

Net Power 541 HP
Engine Model Cat® C18 ™
Bore 5.7 in
Stroke 7.2 in
Displacement 1105 in³
Rated Speed 1,700 rpm
Emissions U.S. EPA Tier 4 Final/EU Stage IV
Gross Power - ISO 14396 580 HP
Net Power - SAE J1349 541 HP
Peak Power Speed 1,500 rpm
Peak Power Speed - 1,500 rpm - Gross - ISO 14396 580 HP
Peak Power Speed - 1,500 rpm - Gross - SAE J1995 588 HP
Peak Power Speed - 1,500 rpm - Net Power - SAE J1349 541 HP
Peak Torque @ (speed) - SAE J1995 2104 ft·lbf
Torque Rise 58%
Operating Specifications
Operating Weight 116362 lb
Rated Payload - Standard (Quarry Face) 12.5 ton (US)
Rated Payload - Loose Material (Standard) 16 ton (US)
Bucket Capacity Range 4.7-13 m3 (6.2-17 yd3)
Operating Weight - High Lift 119618 lb
Operating Weight - Standard 116362 lb
Bucket Capacities 4.7-13 m3 (6.2-17 yd3)
Transmission Type Cat switched reluctance electric drive
Forward 1 (virtual) 4.3 mile/h
Forward 2 (virtual) 7 mile/h
Forward 3 (virtual) 13.8 mile/h
Forward 4 (virtual) 20 mile/h
Reverse 1 (virtual) 4.3 mile/h
Reverse 2 (virtual) 7 mile/h
Reverse 3 (virtual) 17.5 mile/h
Front Fixed
Rear Trunnion
Oscillation Angle 13°
Service Refill Capacities
Fuel Tank 147 gal (US)
Transmission 16 gal (US)
Cooling System - Jacket Water 30 gal (US)
Cooling Systems - Power Train 8 gal (US)
Diesel Exhaust Fluid Tank 8.7 gal (US)
Differential - Final Drives - Front 49 gal (US)
Differential - Final Drives - Rear 49 gal (US)
Engine Crankcase 16 gal (US)
Hydraulic System - Implement/Steering 126 gal (US)
Note All non-road Tier 4 Final/Stage IV diesel engines are required to use: – The machine has the flexibility to run on either ultra-low-sulfur diesel fuel (ULSD with 15 ppm of sulfur or less) or up to B20 biodiesel when feedstock meeting ASTM D7467 specificat
Hydraulic System - Lift/Tilt
Lift Cylinder - Bore 8.7 in
Lift Cylinder - Stroke 41.3 in
Lift/Tilt System - Circuit EH-Positive Flow Control, Flow Sharing
Lift/Tilt System - Pump Variable displacement piston
Maximum Flow at 1,400-1,600 rpm 153 gal/min
Relief Valve Setting - Lift/Tilt 4757 psi
Tilt Cylinder - Bore 8.7 in
Tilt Cylinder - Stroke 27 in
Hydraulic System - Steering
Maximum Flow at 1,400-1,600 rpm 71.3 gal/min
Steering Cut Off Pressure 4351 psi
Steering Cycle Times - High Idle 3.4 s
Steering Cycle Times - Low Idle 5.6 s
Steering System - Circuit Pilot, load sensing
Steering System - Pump Piston, variable displacement
Total Steering Angle 86°
Steering ISO 5010:2007
Hydraulic Cycle Times
Dump 2.2 s
Lower Float Down 3.5 s
Rack Back 4.5 s
Raise 8 s
Total Hydraulic Cycle Time 18.2 s
Sound Performance - Tier 4 Final/Stage IV
Machine Sound Level (ISO 6395) 109 dB(A)
Operator Sound Level (ISO 6396) 72 dB(A)
Note (1) The operator sound pressure level was measured according to the test procedures and conditions specified in ISO 6396:2008. The measurement was conducted at 70 percent of the maximum engine cooling fan speed.
Note (2) Hearing protection may be needed when the machine is operated with a cab that is not properly maintained or when the doors or windows are open for extended periods or in a noisy environment.
Note (3) The machine sound power level was measured according to the test procedures and conditions specified in ISO 6395:2008. The measurement was conducted at 70 percent of the maximum engine cooling fan speed.
Air Conditioning System
Air Conditioning The air conditioning system on this machine contains the fluorinated greenhouse gas refrigerant R134a (Global Warming Potential = 1430). The system contains 1.8 kg of refrigerant which has a CO2 equivalent of 2.574 metric tonnes.
Dimensions (Approximate) - High Lift
B-Pin Height - Maximum Lift 19.3 ft
Clearance at Maximum Lift 12.7 ft
Front Axle Centerline to Bucket Tip 15.9 ft
Ground to Bumper Clearance 3.1 ft
Ground to Center of Axles 3.2 ft
Ground to Lower Hitch Clearance 1.9 ft
Ground to Top of Exhaust Stacks 14.8 ft
Ground to Top of Hood 10.9 ft
Ground to Top of ROPS 13.7 ft
Maximum Overall Height - Bucket Raised 25.8 ft
Maximum Overall Length 41.3 ft
Note Specs are calculated with 6.9 m3 (9.0 yd3) rock bucket and Michelin XLDD2 with 978 mm (3.2 ft) centerline of rear axle height.
Reach - Maximum Lift 7 ft
Rear Axle - Centerline to Bumper 10.5 ft
Wheel Base 14.9 ft
Dimensions (Approximate) - Standard Lift
B-Pin Height - Maximum Lift 18 ft
Clearance at Maximum Lift 11.3 ft
Front Axle Centerline to Bucket Tip 14.7 ft
Ground to Bumper Clearance 3.1 ft
Ground to Center of Axles 3.2 ft
Ground to Lower Hitch Clearance 1.9 ft
Ground to Top of Exhaust Stacks 14.8 ft
Ground to Top of Hood 10.9 ft
Ground to Top of ROPS 13.7 ft
Maximum Overall Height - Bucket Raised 24.5 ft
Maximum Overall Length 40 ft
Note Specs are calculated with 6.9 m3 (9.0 yd3) rock bucket and Michelin XLDD2 with 978 mm (3.2 ft) centerline of rear axle height.
Reach - Maximum Lift 6.8 ft
Rear Axle - Centerline to Bumper 10.5 ft
Wheel Base 14.9 ft
Operator's Cab
ROPS/FOPS ROPS/FOPS meet ISO 3471:2008 and ISO 3449:2005 Level II standards
Brakes ISO 3450:2011


While the electric drive transmission replacement on the 988K enables the significant increase in efficiency, the axles and the driveline are the same as on the proven 988K mechanical drive.

Cat C18 Engine

The Cat C18 engine is built and tested to meet your most demanding applications while meeting Tier 4 Final/Stage IV emission standards.

  • Fully integrated electronic engine controls works in concert with the entire machine to make your fuel go farther.
  • Use less fuel idling with Engine Idle Shutdown.
  • Maximized durability with Delayed Engine Shutdown.
Fuel Efficiency

Enabling maximum productivity and efficiency, all day every day.

The 988K XE systems work hard to make you more efficient through advanced electric drive technology.

  • Overall efficiency improvement of 25 percent.
  • Efficiency improvement of up to 49 percent in tough applications.
  • Up to a 10 percent increase in productivity in load and carry applications.


Cat Switched Reluctance Electric Drive System
  • Continuously variable speed control up to maximum ground speed.
  • Implemented virtual gears for machine controllability.
  • Automatic retarding controls for maintaining speed on grade.
  • Extended maintenance intervals over mechanical power trains.
  • Fewer moving parts than traditional torque converter and mechanical transmission systems.
  • Elimination of the shifting simplifies operator controls thus accelerating the learning curve of new operators.
Cat Switched Reluctance Electric Generator and Pump Drive
  • Fewer moving parts than traditional torque converter systems.
  • Extended maintenance intervals over mechanical power trains.
  • Integrated controls provide power on demand.
  • Integrated pump drive for seamless hydraulic performance.
Cat Integrated Powered Electronics
  • Fully sealed to protect from the elements.
  • Liquid cooled to extend component life.
  • Solid state components maximize durability in extreme conditions.
Cat Switched Reluctance Electric Drive Motor
  • Continuously variable speed control up to maximum ground speed.
  • Implemented virtual gears for machine controllability.
  • Automatic retarding controls for maintaining speed on grade.
  • Extended maintenance intervals over mechanical power trains.
Steering and Transmission Integrated Control System (STIC™)

Experience maximum responsiveness and control with STIC that combines directional selection, virtual gears and steering into a single lever.

Variable Torque Control and Rimpull Control System (RCS)

Lower your cost per ton utilizing advanced torque control and RCS for modulated rimpull.

  • Reduce tire slippage and wear by modulating rimpull from 100 to 25 percent while depressing left pedal. After 25 percent rimpull is achieved the left pedal applies the brake.
  • Reduce the potential for wheel slippage without reducing hydraulic efficiency with RCS.
Automatic Retarding Controls
  • Maintain operator safety and efficiency by controlling speed on grade.
  • Machine sets maximum allowable speed.
  • Operator controls speed up to maximum allowed.


Robust Structures

Your bottom line is improved by highly durable structures that achieve multiple life cycles and withstand the toughest loading conditions.

  • Full box-section rear frame resists torsional shock and twisting forces.
  • Heavy-duty steering cylinder mounts efficiently transmit steering loads into the frame.
  • Axle mounting has been optimized for increased structural integrity.
  • Lower hitch pin, frame plate, and bearing size have been increased for longer life.
Lift Arms
  • Excellent visibility to the bucket edges and work area through a Z-bar design.
  • High load stresses are absorbed by the solid steel lift arms.
  • Enhance strength in key pin areas through the use of one piece castings.
  • Stress relieved lift arms increase durability and lengthen time to repair.
Front Linkage

To ensure long life and reliability, the linkage pin joints feature a greased pin design with an auto lube system attachment available from the factory.


Positive Flow Control Hydraulics

Increase efficiency through our Positive Flow Control (PFC) Hydraulic System. PFC has concurrent pump and valve control. By optimizing pump control, hydraulic oil flow is proportionate to implement lever movement.

  • Fast, productive cycles are enabled by the fully variable implement pump.
  • Increase bucket feel and control through increased hydraulic response.
  • Consistent performance and efficiency with lower system heat.
  • Full hydraulic flow down to 1,400 engine rpm enabled by flow sharing technology.
Electro Hydraulic Controls

Operators increase productivity with our responsive implements feature.

  • Operate comfortably through electronically controlled hydraulic cylinder stops.
  • Handle easy-to-use soft detent controls.
  • Conveniently set automatic implement kickouts from inside the cab.
Steering System

Confident loader operation starts with precise machine control enabled by the 988K XE's load sensing hydraulic steering system.

  • Increase efficiency with our variable displacement piston pumps.
  • Achieve precise positioning for easy loading in tight areas with 43 degrees of steering articulation.
  • Enhance operator comfort with integrated steering and transmission control functions.
Filtration System

Benefit from extended performance and reliability of your hydraulic system with our advanced filtration system.

  • Case drain screens.
  • Hydraulic oil cooler return filter.
  • Pilot filter.
  • In-tank return screens.
  • Axle oil cooler screens if equipped.


Your operators can work more efficiently and stay comfortable with our customer-inspired cab features.

Entry and Exit

Enter and exit the cab easily and safely with these newly designed, ergonomic features.

  • Fold up STIC steer/armrest.
  • 45 degree access stairway angles.
  • Standard stairway lighting.
Deluxe Operator Seat

Enhance comfort and helps reduce operator fatigue with Cat Comfort Series III seat.

  • Heated and ventilated seat featuring leather seat bolster surfaces.
  • High back design and extra thick, contoured cushions.
  • Air suspension system.
  • Easy-to-reach seat levers and controls for six way adjustments.
  • Seat-mounted implement pod and STIC steer that moves with the seat.
  • 76 mm (3 in) wide retractable seat belt.
Control Panel

Ergonomic placement of switches and information display keep your operators comfortable all day every day.

  • Large backlit membrane switches feature LED activation indicators.
  • Switches feature ISO symbols for quick function identification.
  • Two position rocker switch activates the electro hydraulic park brake.

Your operator's productivity is enhanced with our clean, comfortable cab environment.

  • Experience reduced vibrations from isolated cab mounts and seat air suspension.
  • Maintain desired cab temperature with automatic temperature controls.
  • Pressurized cab with filtered air.
  • Low operator sound levels.
  • Convenient floor storage tray/lunch box.


Integrated electronics provide flexible levels of information to both the site and the operator. This integration creates a smart machine and more informed operator, maximizing the productivity of both.

Information Display

We have worked hard to help our customers and operators perform at their best through our newly upgraded touch screen information display.

  • Intuitive operation and easy navigation with our enhanced user interface.
  • Decrease service time by keeping operators informed about machine systems.
Maschinendatenerfassungssystem (Vital Information Management System, VIMS™)

Connect directly to the machine for access to a wide range of sensor information and enhanced machine data.

  • Create productivity reports with payload and work cycle segmentation.
  • Identify operator training needs through productivity data.
  • Detailed data logging of machine parameters and diagnostic codes.
  • Track machine sensor information with trend analysis and histograms to monitor machine health.
Tire Pressure Monitoring System (TPMS)

Tire pressure monitoring is a fully integrated feature which allows operators to monitor inflation of tires. Available through the Information Display, the operator can quickly see the current pressure settings and temperature of each tire.

Система Cat Production Measurement (CPM)

Cat Production Measurement brings payload weighing to the cab so operators can work more productively and deliver accurate loads with confidence. CPM brings advanced weighing modes which assist with payload accuracy and speed the loading cycle.


We can help you succeed by ensuring your 988K XE has design features to reduce your downtime.
  • Efficient electric drive design:
    – Increases engine life, extending time between power train rebuilds
    – Two times the life for power train oil and four times the life for filters
    – Reduces power train rebuild cost
  • Durable SR drive motor, generator, and inverter are built to last through the second engine life, with only the motor and generator requiring the seals and bearings be replaced at the first engine overhaul.
  • Hazardous voltage lamp to assure electric drive system is de-energized and machine is safe to work on.
  • Safe and convenient service with ground level or platform access and grouped service points.
  • Swing-out doors on both sides of the engine compartment provide easy access to important daily service checks.
  • Ecology drains for ease of service and prevention of spills.
  • Reduce downtime with VIMS system notifications so your operators and technicians can resolve any problems before failure.


Legendary Cat Dealer Support

A valued partner, your Cat dealer is available whenever you need them.

  • Preventive maintenance programs and guaranteed maintenance contracts.
  • Best-in-class parts availability.
  • Improve your efficiency with operator training.
  • Genuine Cat Remanufactured parts.


We are constantly improving our products in an effort to provide a safe work environment for the operator and those who work on your job site.

Machine Access
  • Left and right hand stairs with 45 degree angle enhance safety for operators getting on and off the 988K XE.
  • Continuous walkway with non-skid surfaces are designed into the service areas.
  • Maintain three points of contact at all times through ground level or platform accessible service areas.
  • Optional heated mirrors ensure enhanced visibility for safe operation.
  • Standard Cat Vision or optional Cat Detect with radar increase operator awareness around the machine.
  • Optional HID or LED lights provide excellent workspace visibility.
  • Optional cab mounted LED warning beacons.
Operator Environment
  • Reduced vibrations to the operator with isolated cab mounts and seat mounted implement and steering controls.
  • Low interior sound levels.
  • Pressurized cab with filtered air.


Reducing the Impact to the Environment

Sustainability is designed and built into our 988K XE.

  • Maintain the productivity of a 988K mechanical drive machine while operating 25 percent more efficiently.
  • Economy Mode further reduces fuel consumption with minimal impact to productivity.
  • Engine Idle Shutdown can help you save fuel by avoiding unnecessary idling.
  • Reduce waste with our maintenance free batteries.
  • Built for multiple lives, the Cat 988 is one of the most rebuilt products. To assist with maximizing machine life, Caterpillar provides a number of options such as our Reman and Certified Rebuild programs. In these programs, reused or remanufactured components can deliver cost savings of 40 to 70 percent, which lowers operating cost while reducing waste.
  • Electric drive system maximizes consumable life, reducing oil and filter waste.


Efficient Combination

For full truck payloads with minimum loading time, an efficient loading/hauling system starts with a perfect match. Cat wheel loaders are matched with Cat off-highway trucks to maximize volume of material moved at the lowest operating cost per ton. The 988K XE equipped with the standard linkage will pass match the 770 (36 tonnes/40 tons) in 3 passes and the 772 (45 tonnes/50 tons) in 4 passes. Equipped with a high lift linkage the 988K XE is capable of loading a 773 (56 tonnes/61.7 tons) in 5 passes and the 775 (64 tonnes/70 tons) in 6 passes.


Enhance the productivity of your loader and protect your investment in buckets with our Ground Engaging Tools (GET). Your knowledgeable Cat dealer will work with you to understand your application and needs for the GET that is best for you.

Rock Buckets

Designed for use in bank or face loading of limestone and other unprocessed rock. Application also includes truck and hopper loading for a wide range of quarry materials. GET includes spade nose cutting edge with adapters, half arrow segments, bottom wear plates, and sidebar protectors.

Heavy Duty Rock Buckets

Designed for use in applications like face loading tightly compacted pit materials or handling materials of moderate abrasion and high impacts. GET are similar to the rock bucket with the addition of floor liner, half radius liners and bolt-on bottom edge wear plates. 20-series mechanically attached wear plates (MAWPS) are provided for additional wear protection and improved serviceability. Base edge end protection, ski plates, additional side wear plates, wings and an extra set of sidebar protectors are also included.

General Purpose Buckets

Designed for use primarily in stockpiling, re-handling and aggregate applications. GET includes a straight base edge with a bolt-on cutting edge system. Curved sidebars are provided to aid in material retention on the 12.5 yard (9.6 cubic meters) aggregate bucket only.

Coal Buckets

Designed with a larger capacity for use in applications with light density and non-abrasive materials. GET includes a straight base edge with a bolt-on cutting edge system.

Cat Advansys™ Ground Engaging Tools

Protect expensive components. Reduce your operating costs. Get the most out of your machine's performance. Choose from a variety of performance-built Advansys GET like these to meet your application requirements.

  • CapSure™ Sidebar Protector
  • MAWPs – on Side and Bottom
  • Base End Edge Protector
  • CapSure Tip Options: Heavy Duty Tip
  • CapSure Tip Options: Heavy Abrasion Tip
  • CapSure Tip Options: Coal Tip
  • CapSure Tip Options: Heavy Penetration Tip
  • Edge Protection Options: CapSure Shrouds
  • Edge Protection Options: Half Arrow Segment

Please check out our Parts Catalog for more GET options.

CapSure™ Retention Technology

Simplify GET component replacement with hammerless CapSure retention for fast, easy and safe installation. CapSure tips, shrouds and sidebar protectors are easily locked and unlocked with a 180 degree turn of a 3∕4 inch (19 mm) ratchet.

Standard Equipment:

  • Note
    • Standard and optional equipment may vary. Consult your Cat dealer for details.
  • Electrical
    • Alarm, back-up
    • Alternator, single 150 amp
    • Batteries, dry
    • Converter, 10/15 amp, 24V to 12V
    • Lighting system (halogen, work lights, access and service platform lighting)
    • Starting and charging system, 24V
    • Starter emergency start receptacle
    • Starter lockout in bumper
    • Transmission lockout in bumper
    • Hazardous voltage lamp
  • Operator Environment
    • Graphical Information Display, displays real time operating information, performs calibrations and customizes operator settings
    • Air conditioner
    • Cat Detect Vision, rear vision camera system
    • Cab, sound suppressed and pressurized, integrated rollover protective structure (ROPS/FOPS) radio ready for entertainment, includes antenna, speakers and converter (12‑volt 5-amp) and power port
    • Controls, lift and tilt function
    • Heater, defroster
    • Horn, electric
    • Instrumentation, gauges
      – Coolant temperature
      – Engine hour meter
      – Hydraulic oil temperature
      – Power train oil temperature
    • Light, cab, dome
    • Lunchbox, beverage holders
    • CB radio-ready
    • Mirrors, rearview (externally mounted)
    • Rimpull Control System
    • Seat, Cat Comfort Series III, heated and ventilated, air suspension, six-way adjustable
    • Seat belt minder
    • Seat belt, retractable, 76 mm (3 in) wide
    • STIC Control System
    • UV glass
    • Virtual gear indicator
    • Vital Information Management System (VIMS) with Graphical Information Display: External Data Port, Customizable Operator Profiles, Cycle Timer, Integrated Payload Control System
    • Wet-Arm wipers/washers (front and rear)
      – Intermittent front and rear wipers
    • Lights, directional
  • Power Train
    • Brakes, oil-cooled, multi-disc, service/secondary
    • Case drain screens
    • Electro hydraulic parking brake
    • Engine, C18 MEUI diesel, turbocharged/aftercooled
    • Ground level engine shutoff
    • Turbine precleaner, engine air intake
    • Radiator, Aluminum Modular Radiator (AMR)
    • Starting aid, ether, automatic
    • Throttle lock, electronic
    • Manual switch and automatic fuel priming
    • Cat Production Measurement ready
    • Cat SR Generator/Pump Drive
    • Cat SR Drive Motor
    • Cat Integrated Powered Electronics
    • Automatic retarding controls
  • Other
    • Automatic bucket lift kickout/positioner
    • Base machine price includes a rim allowance
    • Hydraulically driven demand fan
    • Couplings, Cat O-ring face seals
    • Doors, service access (locking)
    • Ecology drains for engine, radiator, hydraulic tank
    • Fuel tank, 555 L (147 gal)
    • Hitch, drawbar with pin
    • Hoses, Cat XT
    • Hydraulic, steering and brake filtration/screening system
    • Cat Clean Emission Module
    • Oil sampling valves
    • Premixed 50 percent concentration of extended life coolant with freeze protection to –34° C (–29° F)
    • Rear access to cab and service platform
    • Steering, load sensing
    • Toe kicks
    • Vandalism protection caplocks

Optional Equipment:

  • Note
    • Standard and optional equipment may vary. Consult your Cat dealer for details.
  • Power Train
    • –50° C (–58° F) antifreeze
    • Engine oil change system, high speed, Wiggins
    • Engine block heater 120V or 240V
    • High ambient cooling – software
    • Cat Production Measurement
    • Crankcase guard
  • Operator Environment
    • Cab precleaner
    • AM/FM/CD/MP3 radio
    • Satellite Sirius radio with Bluetooth®
    • LED warning strobe
    • Window pull down visor
    • Handrail mounted mirrors
  • Miscellaneous Attachments
    • Front and rear roading fenders
    • Fast fill fuel system (Shaw-Aero)
    • Cold Weather Starting (extra starter plus two batteries)
    • Aggregate Handler
    • Tire Pressure Monitoring System