Caterpillar 825
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Caterpillar 825

Maintenance schedule, common problems & OEM parts breakdown

The Caterpillar 825 is a full-size articulated soil and landfill compactor built to break down and seal cohesive fill on roadbeds, dams, and landfill working faces using tamping-foot drums front and rear. The current 825 is the direct, letter-dropped successor to the 825K and carries over its Cat C15 engine: 324 kW (435 hp) gross and roughly 302 kW (405 hp) net from a 15.2 L, six-cylinder block. Operating weight runs 35,081-35,528 kg (77,340-78,326 lb) depending on whether the machine carries a Tier 3/Stage IIIA or Tier 4 Final/Stage V emissions configuration. The line traces back to the 824B, renamed 825B in 1970, then carried forward through the 825C, 825G, 825G Series II, 825H, and 825K before Caterpillar dropped the letter for the current-production 825. Caterpillar offers it with an articulated dozer blade up front, tamping-foot (padfoot) drums at each end, and optional single- or multi-drum compaction-measurement instrumentation for grade and density feedback on the go.

Across generations the 825 gained a bigger, cleaner-burning engine and onboard compaction electronics rather than a new chassis concept. The 825H ran a simpler, earlier-tier engine platform; the 825K introduced the C15 with Tier 4 Final aftertreatment (diesel particulate filter, DEF dosing) plus Machine Drive Power compaction measurement, and the current-production 825 carries that same driveline and aftertreatment package forward under a shortened nameplate. For buyers and parts sourcing, that split matters: an 825K-era machine shares engine, hydraulic, and driveline parts with the current 825, while 825H-and-earlier machines do not, since emissions hardware, electronic controls, and several driveline components changed at the K-series jump. Because the model is still in current production, used 825/825K units hold value as landfill and heavy-fill compaction machines, and demand stays steady for tamping-foot tips, drum bearings, and C15 engine/aftertreatment parts across the K-series-to-current run.

Below: full specifications, fluids & capacities, the factory service schedule, common service parts, verified fault codes, what owners discuss, attachment guidance, the complete assembly directory, and a serial-number reference. Complete parts lists with full OEM part numbers, exploded diagrams, quantities, and fitment data are available free in Heavy Parts AI.

Caterpillar 825 specifications

Engine

Engine modelCat C15 (current 825 generation, factory designation 11A)
Gross power324 kW (435 hp) SAE J1995
Net power302 kW (405 hp) SAE J1349 / ISO 9249
Displacement15.2 L (927.6 in³)
Bore x stroke137.2 mm x 171.4 mm (5.4 in x 6.7 in)
Cylinders6, inline
Rated speed1800 rpm
Peak net torque2005 N·m (1479 lbf·ft) at 1300 rpm, 33% torque rise
Emissions tierU.S. EPA Tier 4 Final / EU Stage V / Korea Stage V / Japan 2014 / Brazil MAR-1, or U.S. EPA Tier 3 / EU Stage IIIA equivalent for lesser-regulated markets — same rated power in both configurations

Weights

Operating weight, Tier 4 Final/Stage V35,528 kg (78,326 lb)
Operating weight, Tier 3/Stage IIIA equivalent35,081 kg (77,340 lb)
Drum weight (each)7,333 kg (16,167 lb)
Ground pressurenot published — verify with dealer

Dimensions

Overall length (blade on ground)8.56 m (28.0 ft)
Overall width (over wheels)3.65 m (11.98 ft)
Overall height (to cab roof)4.06 m (13.4 ft)
Overall height (to beacon)4.38 m (14.5 ft)
Wheelbase3.70 m (12.2 ft)
Ground clearance0.49 m (1.7 ft)
Drum diameter1.30 m (4.3 ft)
Drum width1.13 m (3.7 ft)
Wheel outside diameter (over tires)1.67 m (5.5 ft)

Performance

TransmissionPlanetary powershift with electronic clutch pressure control (ECPC), 3 forward / 3 reverse speed ranges
Travel speed, forward5.5 / 10.3 / 17.8 km/h (3.4 / 6.4 / 11.1 mph)
Travel speed, reverse6.6 / 11.8 / 19.7 km/h (4.1 / 7.3 / 12.2 mph)
Hydraulic pump flow117 L/min (30.9 gal/min) at 1800 rpm
Hydraulic main relief pressure26,000 kPa (3,771 psi)
Gradeabilitynot published — verify with dealer

Service capacities (summary)

Fuel tank782 L (206.6 gal)
Hydraulic system134 L (35.4 gal)
Engine oil (crankcase)34 L (9.0 gal)
Cooling system116 L (30.6 gal)
Transmission66 L (17.4 gal)
DEF tank (Tier 4 Final/Stage V)32 L (8.5 gal)

Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.

825 fluids & capacities

SystemCapacityRecommended fluid
Engine crankcase (with filter)34 L (9.0 US gal)Cat DEO-ULS, or oils meeting Cat ECF-3, API CJ-4, and ACEA E9 specifications. Extended 500-hour drain interval applies when running CJ-4 oil. Non-road Tier 4 Final/Stage V engines require ULSD (15 ppm sulfur or less), usable with blends up to 20% biodiesel FAME, or up to 100% renewable diesel/HVO/GTL fuels.
Cooling system116 L (30.6 US gal)Cat Diesel Engine Antifreeze/Coolant (DEAC) or Cat Extended Life Coolant (ELC), factory-filled ethylene glycol base. Standard fill is premixed 50% concentration extended-life coolant rated to -34 C (-29 F); a -50 C (-58 F) concentration is available for extreme cold climates.
Fuel tank782 L (206.6 US gal)Ultra-low sulfur diesel (ULSD, 15 ppm sulfur or less) on Tier 4 Final/Stage V units. Compatible with blends up to 20% biodiesel FAME (up to 100% on engines with no aftertreatment) and up to 100% renewable diesel, HVO, or GTL fuel. Fast-fill tank configuration.
Diesel exhaust fluid (DEF) tank32 L (8.5 US gal)DEF meeting ISO 22241-1:2006. Applies to Tier 4 Final/Stage V configuration only; not fitted on the Tier 3/Stage IIIA-equivalent engine option.
Transmission (planetary powershift, ECPC)66 L (17.4 US gal)Cat TDTO-spec transmission/drivetrain oil per Caterpillar Machine Fluids Recommendations; verify exact grade and viscosity-by-climate chart in the machine's Operation and Maintenance Manual.
Differentials and final drives, front100 L (26.4 US gal)Cat TDTO-spec final drive/axle oil per Caterpillar Machine Fluids Recommendations; front axle is fixed planetary type. Confirm viscosity grade for ambient temperature in the OMM.
Differentials and final drives, rear110 L (29.1 US gal)Cat TDTO-spec final drive/axle oil per Caterpillar Machine Fluids Recommendations; rear axle is oscillating planetary type (+/-8 degrees oscillation). Confirm viscosity grade for ambient temperature in the OMM.
Hydraulic system, tank only134 L (35.4 US gal)Cat HYDO Advanced hydraulic oil; Cat Bio HYDO Advanced (EU Ecolabel-approved biodegradable hydraulic oil) is offered as an alternative fill. Machine runs a total hydraulic filtration system and dedicated hydraulic oil cooler.
Grease (chassis lubrication points)Not specified as a system capacity - applied per fitting per the lubrication chartCat multipurpose grease per Caterpillar Machine Fluids Recommendations; select NLGI grade by ambient temperature per the OMM lubrication chart.

Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.

Caterpillar 825 maintenance schedule

Service intervalTasks
Every 50 h
  • Check engine oil, hydraulic oil, and coolant levels before the daily start (10 hr) and drain water/sediment from the primary fuel filter (water separator).
  • Inspect tamping-foot tips and cutting edges every shift (10 hr); replace any tip that is worn, cracked, or missing before returning the machine to the fill.
  • Test the backup alarm and inspect the turbocharger and seat belt daily (10 hr).
  • Lubricate axle-oscillation and steering-cylinder bearings weekly (50 hr).
  • Clean or replace the cab fresh-air and recirculation filters and drain water/sediment from the fuel tank weekly (50 hr).
Every 250 h
  • Clean the alternator air-vent line/screen and clean or inspect the battery and cables.
  • Inspect drive belts for glazing, cracking, or slip and adjust or replace as needed.
  • Check the brake accumulator precharge and run a full braking-system test.
  • Check differential and final-drive oil level at both end frames.
  • Pull an engine oil sample for used-oil analysis ahead of the next oil change.
Every 500 h
  • Change engine oil and replace the oil filter; pull a Level 1 coolant sample for analysis.
  • Replace the primary fuel filter (water separator) element and the secondary fuel filters; clean the fuel tank cap and strainer.
  • Replace both hydraulic oil filters (main circuit and steering/implement pilot circuit) and pull a hydraulic oil sample.
  • Replace the transmission oil filter and pull a transmission oil sample.
  • Pull a differential and final-drive oil sample from each end frame.
Every 1,000 h
  • Lubricate the articulation-joint bearings and the drive-shaft support bearing.
  • Inspect the ROPS cab structure and mounting hardware for cracks or loose fasteners.
  • Check the service-brake wear indicator and tighten battery hold-down hardware.
Every 2,000 h
  • Change differential and final-drive oil in both end frames.
  • Change hydraulic tank oil and clean the hydraulic-tank breaker relief valve.
  • Check engine valve lash and inspect/adjust the electronic unit injectors.
  • Check brake discs for wear and pull a Level 2 coolant sample.
  • Replace the A/C receiver-dryer.
Every 5,000 h
  • Clean the diesel particulate filter.
  • Replace the DEF injector and the diesel exhaust fluid filter.
  • Replace the DEF-filler breather and, on equipped units, clean the ARD spark plug.
Every 6,000 h
  • Replace the cooling-system water temperature regulator and top off coolant extender (ELC).
  • Replace the seat belt on a 3-year cycle regardless of hours.
  • Replace DEF manifold filters at 10,000 hours and perform a full ELC coolant change at 12,000 hours as the top-end service milestone.

Servicing the 825 beyond the schedule

Predictive Maintenance & Fluid Analysis

Run scheduled oil sampling on the C15 engine, hydraulic system, transmission, and both differential/final-drive housings — the factory schedule pulls engine oil and coolant samples every 250-500 hours and hydraulic/transmission samples every 500 hours. Track trends on iron and silicon to catch tamping-foot drum-bearing wear or driveline contamination before a shaft or bearing lets go. Watch DPF soot load and DEF quality on Tier 4 Final units; degraded DEF or a plugged filter forces regen and derates output on the job.

Corrective & Common Repairs

Expect tamping-foot tip and cutting-edge replacement as the highest-frequency repair — tips see full-perimeter, symmetrical wear from constant forward/reverse impact loading and are inspected every shift. Drive belt, battery cable, and brake-accumulator faults show up around the 250-hour mark. On C15-equipped units, injector adjustment and valve-lash correction come due at 2000 hours; fuel filter and water-separator issues are the most common cause of a no-start or power-loss complaint in the field.

Overhaul & Rebuild Points

Major overhaul targets on the 825 center on the differential/final-drive housings and hydraulic tank, both due for a full oil change at 2000 hours, and the articulation and drive-shaft support bearings that carry the frame-steer loads. Tamping-foot drum and wheel-bearing rebuilds follow tip wear once the drum body itself shows scoring. On the C15, plan engine mid-life work around the turbocharger, injectors, and DPF/DEF aftertreatment components rather than a blanket in-frame overhaul.

Seasonal & Environment Servicing

Cold-weather starts on the C15 depend on ether-start-cylinder condition and coolant strength — check coolant level daily and pull Level 1/2 samples on schedule to guard against freeze-up and liner cavitation. In hot, dusty landfill or fill environments, clean the radiator core and cab air filters more often than the 50-hour default and check the engine air precleaner daily. Wet or abrasive fill accelerates tamping-foot tip wear and axle-oscillation bearing grease-purge intervals.

825 fault codes & troubleshooting

CodeMeaningLikely causeWhat to do
SPN 100 FMI 1Engine oil pressure below normal at current engine speedLow oil level, plugged filter, worn oil pump, or failed oil pressure sensor/wiringCheck oil level and filter condition first; verify sensor wiring before condemning the pump
SPN 110 FMI 0Engine coolant temperature above normal (overheat)Low coolant level, blocked radiator/cooling package, failed fan drive, or faulty thermostatCheck coolant level and radiator core for debris, confirm fan operation before further teardown
SPN 110 FMI 3/4Engine coolant temperature sensor circuit voltage above or below normalOpen or shorted sensor wiring, corroded connector, or failed coolant temp sensorInspect sensor connector and harness for damage or corrosion, test sensor resistance against spec
SPN 190 FMI 8Engine speed sensor signal abnormal (erratic frequency, pulse width, or period)Incorrect sensor air gap, damaged tone ring tooth, or corroded sensor connectorCheck and reset sensor air gap, inspect tone ring for damage, clean or replace connector
SPN 639 FMI 9J1939 data link abnormal update rate between control modulesDamaged or loose data link wiring, poor grounds, or a module dropping off the networkInspect data link harness and connectors, verify module grounds, check for aftermarket wiring taps
SPN 3251 FMI 0Diesel particulate filter soot load above normalExtended idle time, short-cycle duty preventing normal regeneration, or a regeneration inhibited by an operator switchAllow or initiate a parked regeneration; if soot load stays high, check the DPF pressure sensor lines for plugging
SPN 3711 FMI 31Diesel particulate filter active regeneration inhibited due to low exhaust gas temperatureFailed or fouled exhaust gas temperature sensor, or duty cycle too light to reach regeneration temperatureVerify exhaust temp sensor readings against spec, run machine under load to raise exhaust temperature, then retry regen
SPN 3364 FMI 1/2/17Improper diesel exhaust fluid (DEF) quality detected by the aftertreatment systemContaminated, diluted, or expired DEF, or a failed DEF quality sensorDrain and refill with fresh DEF meeting spec, verify quality sensor before replacing aftertreatment components
SPN 168 FMI 1Battery/system voltage below normalWeak or failing battery, loose or corroded ground straps, faulty alternator/charging circuitLoad-test batteries, clean and torque ground connections, check charging system output before replacing the ECM

Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.

825 attachments & work tools

Dozer blade

Standard hydraulic straight (bulldozer-style) blade used to spread fill ahead of compaction, reducing the need for a separate spreader tractor. Moldboard length is about 4.39 m (14.4 ft), max cutting depth about 0.60 m (1.97 ft), and max lift height roughly 0.96-1.04 m (3.1-3.4 ft) depending on how the source measures blade height. Blade has hydraulic tilt, angling roughly 10-11 degrees each direction, powered by double-acting lift and tilt cylinders off the machine's own hydraulic system.

Tamping (pad) foot compaction drums

Primary work tool is the tamping-foot drum itself, not a bolt-on attachment: symmetrical chevron-pattern tips are welded full-perimeter to a base ring that is welded to the drum shell, giving equal compaction in forward and reverse. Standard configuration runs about 65 tips per wheel on a drum roughly 1.31 m (4.3 ft) diameter by 1.13 m (3.7 ft) wide; some dealer literature references a wider high-impact wheel option, but the exact width varies by source and should be confirmed with a dealer.

Cleaner bars

Two adjustable cleaner (scraper) bars per wheel keep carryover soil off the drums in both directions of travel. Offered with standard or abrasive/toothed tips depending on ground conditions, with heat-treated, direct-hardened cutting-edge steel for wear life.

ROPS/FOPS operator protection

Cab is built around an internal four-post rollover and falling-object protective structure (ROPS/FOPS) as standard equipment, not an optional add-on kit, reflecting the compactor's fill-spreading and rough-grade duty cycle.

Mounting and hydraulic arrangement

The 825 is a dedicated integral compactor, not a carrier with a quick-coupler system: the blade mounts via fixed drawbar and hydraulic cylinders to the main frame, and tamping tips are a welded drum feature rather than a swappable shoe kit. All work tools (blade, tips, cleaner bars) draw off the machine's own load-sensing hydraulic and steering circuit; no separate hydraulic kit is needed to run the standard blade.

Technology and guidance options

Factory-offered technology packages include compaction mapping/telematics (grade and pass-count guidance) and machine drive power based compaction control, used to monitor and optimize lift compaction rather than as a physical work tool. Available options and specific packages vary by series and market — confirm current offering with a Cat dealer.

All 825 assemblies by section

Every catalogued assembly group for the Caterpillar 825. Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.

824, 825, 826, 834 & 835 Bulldozers
4j5995 Blade Group
3j7580 Blade Group
6j4663 Blade Group
6j198 Blade Group
6j4654 Blade Group
3j9355 Blade Group
6j6000 Bulldozer Group
6j7261 Bulldozer Group
4j8841 Bulldozer Group
4j9897 Control Valve Group--Type 2
4j9897 Control Valve Group--Type 1
3j7397 Push Cup Group
6j1272 Lift Cylinder Group--6.5" Bore X 36" Stroke
6J***72Cylinder Group-Lift; Lift Cylinder Group1
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4j4498 Tip Cylinder Group--L.H.--6" Bore X 10" Stroke
4j4498 Tip Cylinder Group--L.H.--6" Bore X 10" Stroke--Type 1
4j4498 Tip Cylinder Group--L.H.--6" Bore X 10" Stroke--Type 2
4j4497 Tilt Cylinder Group--R.H.--6.5" Bore X 10" Stroke--Type 1
4j4497 Tilt Cylinder Group--R.H.--6.5" Bore X 10" Stroke
4j4497 Tilt Cylinder Group--R.H.--6.5" Bore X 10" Stroke--Type 2
4j9382 Cylinder Mounting Group
6j5990 Cylinder Mounting Group
3j9179 Cylinder Mounting Group
5j2268 Cylinder Mounting Group
5j8366 Element And Oil Level Indicator Body Group
5J***66Element And Oil Level Indicator Body Group1
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4j9937 External Pilot Check Valve Group
4J***37External Pilot Check Valve Group1
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4j9958 Field Conversion Group--As Viewed From Rear Of Machine
7s9266 Hand Control Group-Type 2
7s9266 Hand Control Group--Type 3
5j81 Hand Control Group
8s1797 Hand Control Group
4j4818 Hand Control Group
7s9266 Hand Control Group-Type 1
5j6758 Hydraulic Control Arrangement
1S***43Implement Lines And Pump Group; Implement Pump And Lines Group1
4J***99Tank And Valve Group1
5J***62Hydraulic Control Group1
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For 834 Tractors Serial No. 43e467-Up
4J***07Hydraulic Lines Group1
6J***80Tank And Valve; Tank And Valve Group1
8S***97Hand Control Group1
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5j7151 Hydraulic Control Arrangement--Field Installation
1S***43Implement Lines And Pump Group; Implement Pump And Lines Group1
4J***58Field Conversion Group1
5J***62Hydraulic Control Group1
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5j7152 Hydraulic Control Arrangement--Field Installation
1S***43Implement Lines And Pump Group; Implement Pump And Lines Group1
4J***58Field Conversion Group1
5J***61Hydraulic Control Group1
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For 835 Compactor Serial No. 44n321-Up
4J***07Hydraulic Lines Group1
6J***80Tank And Valve; Tank And Valve Group1
8J***12Implement Pump Group1
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For 824 Tractors Serial No. 36h685-Up
4J***06Hydraulic Lines Group1
6J***80Tank And Valve; Tank And Valve Group1
8S***97Hand Control Group1
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5j6757 Hydraulic Control Arrangement
1S***43Implement Lines And Pump Group; Implement Pump And Lines Group1
4J***99Tank And Valve Group1
5J***61Hydraulic Control Group1
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For 825b Compactor Serial No. 43n700-Up
4J***06Hydraulic Lines Group1
6J***80Tank And Valve; Tank And Valve Group1
8J***12Implement Pump Group1
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For 824 Tractors Serial No. 36h581-Up
1S***43Implement Lines And Pump Group; Implement Pump And Lines Group1
4J***06Hydraulic Lines Group1
6J***80Tank And Valve; Tank And Valve Group1
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For 834 Tractors Serial No. 43e423-Up
1S***43Implement Lines And Pump Group; Implement Pump And Lines Group1
4J***07Hydraulic Lines Group1
6J***80Tank And Valve; Tank And Valve Group1
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5j462 Hydraulic Control Group
4J***07Hydraulic Lines Group1
5J***81Hand Control Group1
5J***62Hydraulic Control Group1
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5j461 Hydraulic Control Group
4J***06Hydraulic Lines Group1
5J***81Hand Control Group1
5J***61Hydraulic Control Group1
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4j9006 Hydraulic Lines Group--Part 2--Type 2
4j4817 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--First Type
5j3626 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 2
6j1334 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 2--Type 2
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Side Of Bulldozer--Part 1 Of 3--Type 3
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--Type 3
4j4817 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--Second Type
4j9006 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Machine--Part 1--Type 1
4j9007 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Machine--Part One
4j4816 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--Second Type
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--Second Type
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--Type 4
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--Type 4
5j3626 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 2--Type 2
5j3624 Hydraulic Lines Group--Part 1 Of 2--Type 3
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--Type 4
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--Second Type
4j4816 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--Second Type
5j3623 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Type 3
4j9006 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Machine--Part 2--Type 1
4j4816 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--First Type
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--First Type
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--Second Type
5j3623 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Type 2
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--First Type
4j4816 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--Second Type
5j3625 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Type 2
4j4817 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--Second Type
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--Second Type
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--Type 4
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--First Type
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--Type 3
4j9007 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Machine--Part 2--Type 3
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--Type 4
4j4816 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--First Type
5j3623 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Type 1
4j9007 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Machine--Part 1--Type 3
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--Type 3
4j9006 Hydraulic Lines Group--Part 1--Type 3
5j3624 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 2
4j9007 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Machine--Part 2--Type 2
4j4816 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--First Type
5j3624 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 2--Type 2
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--First Type
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--First Type
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--Second Type
4j9007 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Machine--Part Two
4j9006 Hydraulic Lines Group--Part 1--Type 2
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--First Type
6j1334 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 2--Type 3
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--Second Type
6j1334 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 2
5j3625 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Type 1
4j6000 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--Type 3
5j3624 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 2
5j3624 Hydraulic Line Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 2--Type 2
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--Type 4
5j3626 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 2
4j4817 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 3--First Type
5j3626 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2--Type 2
4j4817 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--First Type
4j9565 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 3--Type 3
6j1334 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 2 -- Type 2
4j4817 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 3 Of 3--Second Type
5j3624 Hydraulic Lines Group--Part 2 Of 2--Type 3
6j1334 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 1 Of 2--Type 3
4j9007 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Machine--Part 1--Type 2
6j1334 Hydraulic Lines Group--As Viewed From Rear Right Hand Side Of Bulldozer--Part 2 Of 2
4j9006 Hydraulic Lines Group--Part 2--Type 3
3k9697 Hydraulic Oil Filter Group
5j8365 Hydraulic Oil Filter Group-Type 1
6j9411 Hydaulic Oil Filter Group
5j8365 Hydraulic Oil Filter Group--Type 3
5j8365 Hydraulic Oil Filter Group--Type 2
7j3660 Pin Group
3j6536 Hydraulic Pump Assembly--Type 3
3j6536 Hydraulic Pump Assembly--Type 2
3j6536 Hydraulic Pump Assembly--Type 1
5j1535 Hydraulic Pump Assembly--Type 1
5j1535 Hydraulic Pump Assembly--Type 2
3j9519 Hydraulic Swivel Joint Group--Type 1
3j9519 Hydraulic Swivel Joint Group--Type 2
1s9643 Implement Lines And Pump Group--As Viewed From Right Hand Side Of Machine
1S***43Implement Lines And Pump Group; Implement Pump And Lines Group1
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5s4841 Implement Lines And Pump Group
5S***41Implement Lines And Pump Group; Implement Pump And Lines Group1
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8s6926 Implement Pump And Lines Group--Type 3--Field Installation
8s6925 Implement Pump And Lines Group--Type 2
8s6926 Implement Pump And Lines Group--Type 2
8s6925 Implement Pump And Lines Group
8s6926 Implement Pump And Lines Group--Type 1
8s6925 Implement Pump And Lines Group--Type 3
6j9860 Implement Pump And Mounting Group
6J***60Implement Pump And Mounting Group1
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8j3632 Implement Pump Group
8j3812 Implement Pump Group
8k53 Implement Pump Lines Group--Type-1
8k53 Implement Pump Lines Group--Type 2
8k53 Implement Pump Lines Group
8j3164 Landfill Bulldozer Group
6j1269 Lift Cylinder Group--6.5" Bore X 29.13" Stroke
4j9233 Lift Cylinder Group--(Change 0-4)--4.5" Bore X 22.10" Stroke--Type 1
6j1273 Lift Cylinder Group--6.5" Bore X 36" Stroke
4j9233 Lift Cylinder Group--(Change 5)--4.5" Bore X 22.10" Stroke--Type 2
3j9307 Lift Cylinder Group--6.5" Bore X 36" Stroke
4j7621 Lift Cylinder Group--6.5" Bore X 36" Stroke
4j6005 Lift Cylinder Group--6.5" Bore X 29.13" Stroke
6j1243 Cylinder Mounting Group
5j1556 Pump And Mounting Group
6j9861 Pump And Mounting Group
7j597 Hydraulic Pump Assembly
6j199 Push Arm And Brace Group
3j7579 Push Arm Group--As Viewed From Right Hand Side Of Bulldozer
3j9724 Push Arm Group--As Viewed From Right Hand Side Of Bulldozer
4j4566 Push Cup Group
4j5996 Push Frame Group--Top View
Push Plate
4j9896 Relief Valve Group
4j5841 Spring Housing Group
4j7719 Stabilizer Group
5j4026 Stabilizer Group
9j1559 Stabilizer Group--Heavy Duty--Field Installation
5j4025 Stabilizer Group
6j4666 Stabilizer Group
4j4473 Stabilizer Group
6j3997 Stabilizer Group
6j4665 Stabilizer Mounting Group
3j9832 Stabilizer Mounting Group--First Type
4j4481 Stabilizer Mounting Group--Type 2
4j4481 Stabilizer Mounting Group--Type 1
3j9832 Stabilizer Mounting Group--Second Type
6j3784 Stabilizer Mounting Group
6j7580 Tank And Valve Group-Part 2 Of 3-Type 1
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve Group--Part 3 Of 3--Type 4
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve Group--Part 1 Of 3--Type 3
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve-Part 1 Of 3-Type 1
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve Group--Part 2 Of 3--Type 3
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve Group--Part 2 Of 3--Type 2
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve Group-Part 3 Of 3-Type 1
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve Group--Part 1 Of 3--Type 4
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve Group--Part 3 Of 3--Type 2
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve Group--Part 3 Of 3--Type 3
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve Group--Part 1 Of 3--Type 2
6J***80Tank And Valve; Tank And Valve Group1
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6j7580 Tank And Valve Group--Part 2 Of 3--Type 4
6J***80Tank And Valve; Tank And Valve Group1
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4j9899 Tank And Valve Group--Part 3 Of 3--Type 2
4j9899 Tank And Valve Group--As Viewed From Rear Of Machine--Part 2 Of 3
4j9899 Tank And Valve Group--As Viewed From Rear Of Machine--Part 1 Of 3
6j1336 Tank And Valve Group-Part 3 Of 3-Type 2
6j1336 Tank And Valve Group-Part 2 Of 3-Type 2
4j9899 Tank And Valve Group--As Viewed From Rear Of Machine--Part 1 Of 3--Type 2
4j9899 Tank And Valve Group--As Viewed From Rear Of Machine--Part 3 Of 3
6j1336 Tank And Valve Group--Part 2 Of 3
6j1336 Tank And Valve Group--Part 3 Of 3
6j1336 Tank And Valve Group--Part 1 Of 3--Type 2
6j1336 Tank And Valve Group--As Viewed From Rear Of Machine--Part 1 Of 3
4j9899 Tank And Valve Group--Part 2 Of 3--Type 2
4j6006 Tilt And Tip Cylinder Group--6" Bore X 10.70" Stroke
4j5632 Tip Cylinder Group--6.5" Bore X 10.70" Stroke
6m1027 Trunnion Group--Type 1
6j197 Trunnion Group
4k1750 Trunnion Group--Type 2
4k1750 Trunnion Group
6m1027 Trunnion Group--Type 2
4j6129 Trunnion Mounting Group--Type 1
4j6373 Trunnion Mounting Group
7j7556 Trunnion Mounting Group
6j5980 Trunnion Mounting Group
4j6129 Trunnion Mounting Group--Type 2
4j4572 Check Valve Group
Bulldozer Arrangement
6j7987 824c Bulldozer Arrangement Serial No. 64g1-Up
4J***99Cushion Bulldozer Arrangement1
4J***73Trunnion Mounting Group1
4J***65Hydraulic Lines Group1
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6j1276 824c Bulldozer Arrangement Serial No. 64g1-Up
4J***18Hand Control Group1
4J***99Cushion Bulldozer Arrangement1
4J***73Trunnion Mounting Group1
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4j6595 824c Bulldozer Arrangement Serial No. 64g1-Up
3J***79Cylinder Mounting Group1
4J***18Hand Control Group1
4J***99Cushion Bulldozer Arrangement1
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6j4748 824s Bulldozer Arrangement Serial No. 35g551-Up
4K***50Trunnion Group1
5J***24Hydraulic Lines Group1
6J***43Mounting Group-Lift Cylinder1
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4j4603 824s Bulldozer Arrangement Serial No. 35g1-Up
3J***79Cylinder Mounting Group1
3J***07Lift Cylinder Group1
3J***73Straight Bulldozer Arrangement1
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6j1245 824s Bulldozer Arrangement Serial No. 35g1 To 35g228
4J***81Stabilizer Mounting Group1
4J***18Hand Control Group1
4K***50Trunnion Group1
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6j9503 824s Bulldozer Arrangement Serial No. 35g229 To
4J***81Stabilizer Mounting Group1
4K***50Trunnion Group1
5J***24Hydraulic Lines Group1
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6j1244 834 Bulldozer Arrangement Serial No. 36g1 To 36g176,
3J***32Stabilizer Mounting Group1
4J***18Hand Control Group1
5J***26Hydraulic Lines Group1
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4j6004 834c Bulldozer Arrangement Serial No. 64g1-Up
3J***79Cylinder Mounting Group1
4J***18Hand Control Group1
4J***99Cushion Bulldozer Arrangement1
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6j1277 834c Bulldozer Arrangement Serial No. 64g1-Up
4J***18Hand Control Group1
4J***99Cushion Bulldozer Arrangement1
4J***00Hydraulic Lines Group1
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6j7985 834c Bulldozer Arrangement Serial No. 64g1-Up
4J***99Cushion Bulldozer Arrangement1
4J***00Hydraulic Lines Group1
4J***29Trunnion Mounting Group1
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6j1275 Bulldozer Arrangement Serial No. 88h1-Up
6J***97Trunnion Group1
6J***01Bulldozer Arrangement1
6J***43Mounting Group-Lift Cylinder1
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4j4602 834s Bulldozer Arrangement Serial No. 36g1-Up
3J***79Cylinder Mounting Group1
3J***74Straight Bulldozer Arrangement1
3J***32Stabilizer Mounting Group1
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5j511 824f Bulldozer Arrangement Serial No. 93g1-Up
4J***33Lift Cylinder Group1
4J***82Cylinder Mounting Group1
5J***11Bulldozer Arrangement1
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5j510 834f Bulldozer Arrangement Serial No. 93g1-Up
4J***33Lift Cylinder Group1
4J***82Cylinder Mounting Group1
5J***10Bulldozer Arrangement1
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6j9504 834s Bulldozer Arrangement Serial No. 36g177 To
3J***32Stabilizer Mounting Group1
5J***26Hydraulic Lines Group1
5J***68Straight Bulldozer Arrangement1
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6j6837 824f Or 825f Bulldozer Arrangement Serial No.
4J***33Lift Cylinder Group1
5J***14Film 824f1
6J***90Cylinder Mounting Group1
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7j4881 Bulldozer Arrangement
6J***80Trunnion Mounting Group1
6J***63Bulldozer Arrangement; 834f Or 835f Bulldozer Arrangement1
7J***81Bulldozer Arrangement1
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7j4880 Bulldozer Arrangement
6J***37Bulldozer Arrangement; 824f Or 825f Bulldozer Arrangement0
7J***80Bulldozer Arrangement1
7J***56Trunnion Mounting Group0
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6j201 Bulldozer Arrangement
6J***98Blade Group1
6J***99Push Arm And Brace Group1
6J***01Bulldozer Arrangement1
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6j202 Bulldozer Arrangement Serial No. 88h1-Up
4J***21Lift Cylinder Group1
5J***68Cylinder Mounting Group1
6J***97Trunnion Group1
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6j4749 834s Bulldozer Arrangement Serial No. 36g310-Up
5J***26Hydraulic Lines Group1
6J***43Mounting Group-Lift Cylinder1
6J***72Cylinder Group-Lift; Lift Cylinder Group1
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6j7263 834f Or 835f Bulldozer Arrangement Serial No.
4J***33Lift Cylinder Group1
5J***13Film 834f1
6J***90Cylinder Mounting Group1
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4j5999 Cushion Bulldozer Arrangement
4J***32Tip Cylinder Group1
4J***41Spring Housing Group1
4J***95Blade Group1
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9j4477 Fill Spreading Bulldozer Arrangement
4J***06Hydraulic Lines Group1
4J***33Lift Cylinder Group1
6J***36Fill Spreading Bulldozer Arrangement1
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5j512 Fill Spreading Bulldozer Arrangement
4J***41Bulldozer Group1
5J***12Fill Spreading Bulldozer Arrangement1
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6j7262 Fill Spreading Bulldozer Arrangement
6J***61Bulldozer Group1
6J***62Fill Spreading Bulldozer Arrangement1
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6j6836 Fill Spreading Bulldozer Arrangement. Part Of
6J***00Bulldozer Group1
6J***36Fill Spreading Bulldozer Arrangement1
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9j5230 Fill Spreading Bulldozer Arrangement
7J***56Trunnion Mounting Group1
9J***77Fill Spreading Bulldozer Arrangement1
9J***30Fill Spreading Bulldozer Arrangement1
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8s7083 Hydraulic Control Arrangement--Type 2
6J***34Hydraulic Lines Group1
6J***80Tank And Valve; Tank And Valve Group1
8J***32Implement Pump Group1
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8s7083 Hydraulic Control Arrangement--Type 1
6J***34Hydraulic Lines Group1
6J***80Tank And Valve; Tank And Valve Group1
8S***97Hand Control Group1
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8s1904 Hydraulic Control Arrangement
5S***41Implement Lines And Pump Group; Implement Pump And Lines Group1
6J***34Hydraulic Lines Group1
6J***80Tank And Valve; Tank And Valve Group1
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6j1338 Hydraulic Control Group Serial No. 36h1 To 36h580
5J***81Hand Control Group1
5S***41Implement Lines And Pump Group; Implement Pump And Lines Group1
6J***34Hydraulic Lines Group1
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3j9574 Straight Bulldozer Arrangement
3J***55Blade Group1
3J***74Straight Bulldozer Arrangement1
3J***24Push Arm Group; Push Arm Group1
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5j3668 Straight Bulldozer Arrangement
3J***55Blade Group1
3J***24Push Arm Group; Push Arm Group1
4J***97Cylinder Group-Tilt-Rh; -Rh1
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3j9573 Straight Bulldozer Arrangement
3J***79Push Arm Group; Push Arm Group1
3J***80Blade Group1
3J***73Straight Bulldozer Arrangement1
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6j4747 Straight Bulldozer Arrangement
3J***24Push Arm Group; Push Arm Group1
4J***97Cylinder Group-Tilt-Rh; -Rh1
4J***98Cylinder Group-Lift1
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5j3667 Straight Bulldozer Arrangement
3J***79Push Arm Group; Push Arm Group1
3J***80Blade Group1
4J***73Stabilizer Group1
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6j4750 Straight Bulldozer Arrangement
3J***79Push Arm Group; Push Arm Group1
4J***97Cylinder Group-Tilt-Rh; -Rh1
4J***98Cylinder Group-Lift1
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825 serial number reference

The PIN plate is a riveted metal tag on the machine's articulated main frame, usually near the front frame/articulation joint or on the frame rail below the cab on the operator's side. Read the first 3 characters of the PIN as the serial prefix (identifies model and plant), with the remaining digits as the sequential machine serial running from that prefix upward.

PrefixIdentifies
43N, 52K825B (renamed from 824B, 1970)
86X825C
6RN825G
AXB825G Series II
AZW825H
233, SEE, 2L9, 2T9825K

Frequently asked questions

What engine powers the Caterpillar 825?

A Cat C15 diesel producing 324 kW (435 hp) gross and roughly 302 kW (405 hp) net from a 15.2 L (927 in3), six-cylinder inline block. Tier 4 Final/Stage V units add diesel particulate filter and DEF aftertreatment; Tier 3/Stage IIIA configurations run without it.

What is the operating weight of the Caterpillar 825?

Operating weight runs 35,081-35,528 kg (77,340-78,326 lb) depending on emissions configuration, with Tier 3/Stage IIIA machines at the lower end and Tier 4 Final/Stage V machines with full aftertreatment at the upper end.

What replaced the Caterpillar 825?

Nothing has yet — the current 825 is itself the direct successor to the 825K, with the model letter simply dropped for the present generation. It carries the 825K's C15 engine, operating weight range, and tamping-foot drum design forward essentially unchanged.

What 825 owners discuss

What do operators say about the 825's powertrain and shift behavior?
The compactor carries the same power-shift transmission philosophy and torque-converter lock-up clutch used on Cat's large wheel-loader line, and operators note it runs as a four-speed box with the top gear disabled for this application - so driveline wear patterns and fluid specs track more closely to the loader family than the model number alone suggests. Auto-shift is generally left on for travel between cells or lifts, but many operators disable it for tight in-place tamping, since the lock-up clutch can hunt between gears at walking speed on soft fill. Confirm shift-table behavior against the operator manual before assuming loader components interchange - have your dealer verify ratios and spline counts before ordering.
What hydraulic quirks or leaks come up most in owner discussions?
Seepage at the articulation cylinder rod seals and steering valve fittings is the most reported hydraulic complaint as hours climb; dirt packed around the hitch hides a slow leak until the reservoir is already low, so operators are told to wipe the joint down before every walk-around rather than eyeball it dirty. Because steering runs load-sensing with electronically controlled cylinder stops, sluggish or jerky turn response more often traces to a dirty pilot filter or a marginal pressure sensor than to the main pump itself. A hot hydraulic-temperature gauge in normal ambient conditions is read as a plugged cooler core or a slipping charge pump before anyone condemns the piston pump.
What wear pattern shows up on the tamping-foot drums and cleaner bars?
Tamping tips wear evenly front and back given the symmetrical pattern, and owners watch for tip rounding as the first visible sign that compaction quality is dropping - tips are replaced individually rather than swapping a whole drum. In wet clay or high-fines fill, the cleaner bars riding between the pad rows are the part people watch closest: once a bar cracks or its edge dubs over, the drum starts carrying a ball of mud and compaction effectively stops until the drum is scraped clean or the bar is swapped. Standard cleaner-bar tips hold up fine on typical fill; abrasive-tip bars are the common upgrade for rocky or high-silica material.
Are there known engine quirks tied to the C15 that owners should expect?
The 825 runs the same C15 ACERT engine family used across Cat's on-highway and off-highway lineup, so the quirks reported mirror what's documented industry-wide for that engine: intake valve actuator wiring and connector faults that show up as hard-start or rough-run codes, and turbo wastegate/actuator drift that throws low-boost or overboost codes. Aftertreatment regen trouble - stalled, extended, or failed regens and the related fault codes - tends to surface more on units run at light load for long stretches, since creeping or idling through fine-grade work doesn't always get exhaust temperature up for a clean passive regen. None of this is unique to the compactor duty cycle, it's the same C15 ACERT profile carried over from other applications. Have your dealer verify any turbo, intake valve actuator wiring, or aftertreatment fault code before assuming a bigger engine problem.
What electrical or sensor issues come up most with the compaction-control and MDP system?
The Machine Drive Power compaction-measurement system leans on wheel-speed and drivetrain-torque inputs, and owners report the compaction readout or map going flat or erratic well before any real mechanical fault shows - loose harness connectors and corroded pins at the drum-to-frame joints are the usual root cause, since that wiring run sits exposed to mud, moisture, and regular wash-down. General electrical gremlins on this class of machine more often start at ground straps and bulkhead connectors than at the control module itself. Have your dealer verify MDP calibration and trace any persistent electrical fault code before a control module gets replaced.
What should I check on the articulation hitch and center pin?
Play at the center articulation joint and its lock/lube points is a daily inspection item since this joint carries the full steering load. Reported symptoms include looseness felt under load, oil weeping at the hitch cap, and a squeal or thump on lock-to-lock turns; grease intervals are often shortened on machines that sit idle between shifts or run heavy in-place tamping cycles. Have your dealer verify articulation pin and lock condition before continuing to run a machine that shows hitch play or leakage - this is a steering-safety item, not a routine wear item to defer.
What should I check before buying a used 825?
Compare hour meter against overall paint, decal, and seat wear rather than trusting the display alone. Pull service and regen history if the seller has it, and check for any recurring turbo, intake valve actuator, or aftertreatment fault codes in the ECM history. Walk the drums for tamping-tip rounding and cleaner-bar condition, check for oil weep at the drum bearing housings, and inspect the articulation hitch for play and leakage. Cycle the transmission through its full shift range and confirm auto-shift and lock-up behave smoothly at low travel speed. If the compaction-control/MDP option is fitted, confirm it powers up and calibrates rather than assuming the display alone proves the system works. Get a dealer pre-purchase inspection before finalizing - have your dealer verify hydraulic, driveline, and aftertreatment condition on any used unit.

Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.

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