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Komatsu PC78UU-8 and PC88MR-8 specifications

Entries in this reference
Listing-entry count
2
Short answer

Komatsu PC78UU-8 and PC88MR-8: full-size excavators.

Selected configuration figures
ConfigurationDocumented field and quantity
PC78UU-8
Horsepower, Gross-SAE J1995
57.7 hp
Operating Weight
17,549 lb
PC88MR-8
Horsepower, Gross-SAE J1995
68 hp
Operating Weight
18,133 lb
PC78UU-8 and PC88MR-8 specification matrix — Listing labels reported by the source
Publisher nameSource guideListing-entry countLabels named by the source
KomatsuPC78UU-8 and PC88MR-82PC78UU-8 and PC88MR-8
Dimensions and weight
SpecificationPC78UU-8PC88MR-8
Track Gauge6.14 ft6.14 ft
Track Length On Ground7.34 ft7.34 ft
Overall Height8.96 ft8.96 ft
Overall Length19.89 ft20.26 ft
Overall Track Width7.62 ft7.62 ft
SpecificationPC88MR-8
Length Of Track On Ground7.34 ft
Ground Clearance2.42 ft
Tail Swing Radius4.38 ft
Removal Counterweight Clearance2.42 ft
Undercarriage
SpecificationPC78UU-8PC88MR-8
Shoe Size17.72 in17.72 in
Shoe TypeRoadlinerRoadliner
Number Of Carrier Rollers Per Side11
Number Of Track Rollers Per Side55
SpecificationPC78UU-8
Ground Pressure0.69 psi
Adjustment Of The Track TensionGrease
Number Of Shoes Per Side39
SpecificationPC88MR-8
Seal Of TrackSealed track
Number Of Shoes (Each Side)39
Track AdjusterHydraulic
Track FrameBox-section
Centre FrameX-frame
Electrical System
SpecificationPC78UU-8
Alternator25 A
Starter3.0 kw
Battery55 Ah
Engine
SpecificationPC78UU-8PC88MR-8
Horsepower, Gross-SAE J199557.7 hp68 hp
Horsepower, Net-ISO 924955 hp65.8 hp
Horsepower, Net-SAE J134955 hp65.8 hp
Number Of Cylinders44
Engine ModelSAA4D95LE-5SAA4D95LE-5
Engine TypeWater-cooled,4-cycle,Direct InjectionWater-cooled,4-cycle
Power Measured @1,950 rpm1,950 rpm
Displacement199 cu in199 cu in
AspirationTurbochargedTurbocharged, and air-to-air aftercooled
Fan Drive TypeMechanicalMechanical
SpecificationPC88MR-8
Lubrication SystemMethod- Gear pump, force-lubrication; Filter-Full-flow
Starter Motor4.5 kW
Battery55 Ah/2 x 12 V
Air CleanerDry-type with double elements and auto dust evacuator, plus dust indicator
GovernorAll-speed control, electronic
Alternator35 A/24 V amps
Bore And Stroke95 mm x 115 mm 3.74\" x 4.53\"
Fuel SystemDirect injection
Driveline
SpecificationPC78UU-8PC88MR-8
Drawbar Pull, Maximum (Kg)68206820
Travel Speed2.9/5.02.9/5.0
Capacities
SpecificationPC78UU-8PC88MR-8
Fuel Tank33.1 gal33.1 gal
Engine Oil2 gal3.1 gal
Radiator2.8 gal2.7 gal
Hydraulic29.1 gal26.5 gal
SpecificationPC88MR-8
Swing Drive0.8 gal
Final Drive0.3 gal
Operational
SpecificationPC78UU-8PC88MR-8
Swing Speed1,340 rpm1,335 rpm
Boom Size12.3 ft11.2 ft
Boom TypeStandardStandard
Arm Size5.7 ft5.5 ft
Bucket Crowd Force – ISO62506250
Arm TypeStandardStandard
Bucket Size – Kga Standard Gp0.3 yd30.3 yd3
Arm Crowd Force – ISO39603960
Digging Reach – Maximum21 ft22.8 ft
Digging Depth – Maximum13.9 ft13.7 ft
Maximum Reach @ Ground Level20.5 ft22.1 ft
Swing Mechanism
SpecificationPC78UU-8
Swing Speed10 rpm
Weights
SpecificationPC78UU-8PC88MR-8
Operating Weight17,549 lb18,133 lb
Bucket Weight - Kga Gp456.4 lb456.4 lb
Quick Hitch Weight – Kga231.5 lb231.5 lb
Hydraulic System
SpecificationPC78UU-8PC88MR-8
Hydraulic System TypeHydrauMind SystemHydrauMind System
Selectable Work Modes55
Economy Sub-Mode Selections44
Main Pump TypeVariable displacement, axial pistonVariable displacement, axial piston
SpecificationPC88MR-8
Maximum Flow Rate42.3 gpm
Hydraulic Motor (Travel)2 x piston motor with parking brake
Hydraulic Motor (Swing)1 x piston motor with swing holding brake
Swing System
SpecificationPC88MR-8
Swing ReductionPlanetary gear
Swing Circle LubricationGrease-bathed
Driven ByHydraulic motor
Swing LockMechanical disc brake
Brakes
SpecificationPC88MR-8
Parking BrakeMechanical disc
Service BrakeHydraulic lock
Variants — Source comparison annotation
Source guideDiffering-field count reported
PC78UU-8 and PC88MR-851
Ratios
FigurePC78UU-8PC88MR-8
Engine horsepower per 1,000 lb of weight3.13.6
Fuel tank per engine horsepower0.60 gal0.50 gal
Reference directory classification
Equipment groupfull-size excavator
PC78UU-8 and PC88MR-8: forum references — Forum-title search
Forum indexEquipment class queriedNames in the searchMatching titles
Heavy Equipment Forumsfull-size excavatorKomatsu and the PC78UU line that the PC78UU-8, PC88MR-8 belongs to (no title names the exact model). That is too few titles to say what owners mostly ask about, so the most recent are listed instead5
Used market for the PC78UU-8 and PC88MR-8 — Dated first-page listing snapshot
Observation dateListing sourceEquipment searchListings
2026-09-24MachineryTraderKomatsu full-size excavator5
ModelListedModel yearsLowest askingHighest askingMedian askingMedian hours
PC88MR-852010 to 2015$28,000$33,943$29,46412,837
PC78UU-8 and PC88MR-8: recall reference — Dated CPSC search
Search dateDatabaseNames queriedSearch result
2026-09-24U.S. Consumer Product Safety CommissionKomatsu together with the full-size excavator PC78UU-8, PC88MR-8No matching recall in this search

Sources for this page

Evidence classDocument, classification and recorded date
Reference site
Reference site
Forum threads
Used-market listings
Federal agency data
Recorded observations — Forum-title snapshot
Observation fieldRecorded value
Title count5
Forum indexesHeavy Equipment Forums
Search wordingthe PC78UU-8 and PC88MR-8 full-size excavator
Topics in the title resultshydraulics
Latest title quoted by the referenceKomatsu Pc88mr 8 Auxiliary Hydraulic Valves Sticking

Komatsu PC78UU-8 and PC88MR-8: Configuration records

PC78UU-8
SpecificationSource figure
Dimensions and weight
Track Length On Ground7.34 ft
Overall Height8.96 ft
Overall Length19.89 ft
Overall Track Width7.62 ft
Undercarriage
Shoe Size17.72 in
Ground Pressure0.69 psi
Number Of Carrier Rollers Per Side1
Number Of Shoes Per Side39
Number Of Track Rollers Per Side5
Adjustment Of The Track TensionGrease
Shoe TypeRoadliner
Engine
Engine ModelSAA4D95LE-5
Displacement199 cu in
Number Of Cylinders4
Power Measured @1,950 rpm
AspirationTurbocharged
Horsepower, Gross-SAE J199557.7 hp
Horsepower, Net-ISO 924955 hp
Horsepower, Net-SAE J134955 hp
Engine TypeWater-cooled,4-cycle,Direct Injection
Fan Drive TypeMechanical
Operational
Boom Size12.3 ft
Boom TypeStandard
Arm Size5.7 ft
Bucket Crowd Force – ISO6250
Arm TypeStandard
Bucket Size – Kga Standard Gp0.3 yd3
Arm Crowd Force – ISO3960
Digging Reach – Maximum21 ft
Digging Depth – Maximum13.9 ft
Maximum Reach @ Ground Level20.5 ft
Electrical System
Starter3.0 kw
Driveline
Drawbar Pull, Maximum (Kg)6820
Travel Speed2.9/5.0
Capacities
Fuel Tank33.1 gal
Engine Oil2 gal
Radiator2.8 gal
Hydraulic29.1 gal
Weights
Bucket Weight - Kga Gp456.4 lb
Quick Hitch Weight – Kga231.5 lb
Hydraulic System
Hydraulic System TypeHydrauMind System
Selectable Work Modes5
Economy Sub-Mode Selections4
Main Pump TypeVariable displacement, axial piston
Additional specifications
Track Gauge6.14 ft
Swing Speed1,340 rpm
Alternator25 A
Battery55 Ah
Operating Weight17,549 lb

Source

PC88MR-8
SpecificationSource figure
Dimensions and weight
Length Of Track On Ground7.34 ft
Ground Clearance2.42 ft
Tail Swing Radius4.38 ft
Removal Counterweight Clearance2.42 ft
Track Length On Ground7.34 ft
Overall Height8.96 ft
Overall Length20.26 ft
Overall Track Width7.62 ft
Undercarriage
Shoe Size17.72 in
Number Of Carrier Rollers Per Side1
Number Of Track Rollers Per Side5
Shoe TypeRoadliner
Seal Of TrackSealed track
Number Of Shoes (Each Side)39
Track AdjusterHydraulic
Track FrameBox-section
Centre FrameX-frame
Engine
Engine ModelSAA4D95LE-5
Displacement199 cu in
Number Of Cylinders4
Power Measured @1,950 rpm
AspirationTurbocharged, and air-to-air aftercooled
Horsepower, Gross-SAE J199568 hp
Horsepower, Net-ISO 924965.8 hp
Horsepower, Net-SAE J134965.8 hp
Engine TypeWater-cooled,4-cycle
Fan Drive TypeMechanical
Lubrication SystemMethod- Gear pump, force-lubrication; Filter-Full-flow
Air CleanerDry-type with double elements and auto dust evacuator, plus dust indicator
GovernorAll-speed control, electronic
Bore And Stroke95 mm x 115 mm 3.74" x 4.53"
Fuel SystemDirect injection
Operational
Boom Size11.2 ft
Boom TypeStandard
Arm Size5.5 ft
Bucket Crowd Force – ISO6250
Arm TypeStandard
Bucket Size – Kga Standard Gp0.3 yd3
Arm Crowd Force – ISO3960
Digging Reach – Maximum22.8 ft
Digging Depth – Maximum13.7 ft
Maximum Reach @ Ground Level22.1 ft
Driveline
Drawbar Pull, Maximum (Kg)6820
Travel Speed2.9/5.0
Capacities
Fuel Tank33.1 gal
Engine Oil3.1 gal
Radiator2.7 gal
Hydraulic26.5 gal
Swing Drive0.8 gal
Final Drive0.3 gal
Weights
Bucket Weight - Kga Gp456.4 lb
Quick Hitch Weight – Kga231.5 lb
Hydraulic System
Hydraulic System TypeHydrauMind System
Selectable Work Modes5
Economy Sub-Mode Selections4
Main Pump TypeVariable displacement, axial piston
Maximum Flow Rate42.3 gpm
Hydraulic Motor (Travel)2 x piston motor with parking brake
Hydraulic Motor (Swing)1 x piston motor with swing holding brake
Swing System
Swing ReductionPlanetary gear
Swing Circle LubricationGrease-bathed
Driven ByHydraulic motor
Swing LockMechanical disc brake
Brakes
Parking BrakeMechanical disc
Service BrakeHydraulic lock
Additional specifications
Track Gauge6.14 ft
Starter Motor4.5 kW
Battery55 Ah/2 x 12 V
Alternator35 A/24 V amps
Swing Speed1,335 rpm
Operating Weight18,133 lb

Source

Compare Komatsu PC78UU-8, PC88MR-8
Dimensions and weight
SpecificationPC78UU-8PC88MR-8
Track Gauge6.14 ft6.14 ft
Track Length On Ground7.34 ft7.34 ft
Overall Height8.96 ft8.96 ft
Overall Length19.89 ft20.26 ft
Overall Track Width7.62 ft7.62 ft
Undercarriage
SpecificationPC78UU-8PC88MR-8
Shoe Size17.72 in17.72 in
Shoe TypeRoadlinerRoadliner
Number Of Carrier Rollers Per Side11
Number Of Track Rollers Per Side55
Engine
SpecificationPC78UU-8PC88MR-8
Horsepower, Gross-SAE J199557.7 hp68 hp
Horsepower, Net-ISO 924955 hp65.8 hp
Horsepower, Net-SAE J134955 hp65.8 hp
Number Of Cylinders44
Engine ModelSAA4D95LE-5SAA4D95LE-5
Engine TypeWater-cooled,4-cycle,Direct InjectionWater-cooled,4-cycle
Power Measured @1,950 rpm1,950 rpm
Displacement199 cu in199 cu in
AspirationTurbochargedTurbocharged, and air-to-air aftercooled
Fan Drive TypeMechanicalMechanical
Driveline
SpecificationPC78UU-8PC88MR-8
Drawbar Pull, Maximum (Kg)68206820
Travel Speed2.9/5.02.9/5.0
Capacities
SpecificationPC78UU-8PC88MR-8
Fuel Tank33.1 gal33.1 gal
Engine Oil2 gal3.1 gal
Radiator2.8 gal2.7 gal
Hydraulic29.1 gal26.5 gal
Operational
SpecificationPC78UU-8PC88MR-8
Swing Speed1,340 rpm1,335 rpm
Boom Size12.3 ft11.2 ft
Boom TypeStandardStandard
Arm Size5.7 ft5.5 ft
Bucket Crowd Force – ISO62506250
Arm TypeStandardStandard
Bucket Size – Kga Standard Gp0.3 yd30.3 yd3
Arm Crowd Force – ISO39603960
Digging Reach – Maximum21 ft22.8 ft
Digging Depth – Maximum13.9 ft13.7 ft
Maximum Reach @ Ground Level20.5 ft22.1 ft
Weights
SpecificationPC78UU-8PC88MR-8
Operating Weight17,549 lb18,133 lb
Bucket Weight - Kga Gp456.4 lb456.4 lb
Quick Hitch Weight – Kga231.5 lb231.5 lb
Hydraulic System
SpecificationPC78UU-8PC88MR-8
Hydraulic System TypeHydrauMind SystemHydrauMind System
Selectable Work Modes55
Economy Sub-Mode Selections44
Main Pump TypeVariable displacement, axial pistonVariable displacement, axial piston

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