Caterpillar PR-105
Maintenance schedule, common problems & OEM parts breakdown
The Caterpillar PR-105 is a wheeled cold planer, also marketed as a pavement profiler, built by CMI Corporation for Caterpillar under an OEM agreement dating to the mid-1980s. It runs a naturally aspirated Caterpillar 3204 diesel rated at roughly 89.9 hp (67 kW) gross, and carries an operating weight of about 7,710 kg (17,000 lb). It shares its 5WC serial-number prefix with the closely related PR-100 and PR-100DC pavement profilers, and sits within Caterpillar's original PR-series lineup alongside the PR-75, PR-275, PR-450, and PR-750B. The PR-105 is an open-station, non-tracked (wheeled) machine with a water spray system for drum cooling and dust control; cutting width and depth figures are reported inconsistently across documentation, so treat any specific number as unconfirmed until verified against the physical drum or dealer records.
Caterpillar's PR-series was a short-lived, CMI-built product line from the pre-ECM era: fully mechanical fuel system, hydro-mechanical drum and wheel drive, and no electronic diagnostics of any kind. Within a decade Caterpillar shifted cold-planer production toward its own PM-series machines, which moved to tracked undercarriages, larger engines, and electronic controls, effectively retiring the PR-series without a direct one-for-one successor. That makes the PR-105 a niche survivor today: few remain in service, documentation is thin, and parts support leans heavily on Cat 3204 engine channels and general CMI Roto-Mill cross-references rather than dedicated PR-105 literature. For buyers and rebuilders, its value is as a simple, low-cost entry point for small-scale milling work (driveways, patches, parking lots) where a fully electronic modern planer is overkill.
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 PR-105 specifications
Engine
| Engine model | Cat 3204, four-cylinder diesel (naturally aspirated version used in this early utility-class cold planer) |
| Gross power | approx. 67 kW (89.9 hp) — not independently cross-verified, treat as approximate |
| Displacement | 5.2 L (317 cu in) or 4.4 L (269 cu in) depending on the reference used for this engine family — varies by configuration/series, verify with dealer |
| Cylinders | 4, inline |
| Emissions tier | not published — this is a pre-emissions-regulation era mechanical diesel, no tier rating documented |
Weights
| Operating weight (full load) | approx. 7,710 kg (17,000 lb) |
| Shipping weight | not separately published — likely close to operating weight for this class of machine |
| Ground pressure | not published |
Dimensions
| Shipping length | approx. 3.58 m (11.75 ft) |
| Shipping width | approx. 2.52 m (8.26 ft) |
| Shipping height | approx. 2.92 m (9.59 ft) |
| Undercarriage | wheeled machine, not track-mounted |
| Wheelbase / track gauge | not published |
| Ground clearance | not published |
Performance
| Travel speed | approx. 8 km/h (5 mph) — not independently cross-verified, treat as approximate |
| Milling (operating) speed | roughly 45-135 m/min — varies by configuration/series, treat as unconfirmed until verified against the unit |
| Cutting width | figures range from roughly 330 mm (13 in) up to 1905 mm (75 in) — varies by configuration/series, not confirmed for this specific model; verify with dealer before quoting |
| Cutting depth | approx. 150 mm (6 in) or 254 mm (10 in) — varies by configuration/series, not confirmed |
| Gradeability | not published |
Service capacities (summary)
| Fuel tank | approx. 212 L (56.1 gal) — not independently cross-verified, treat as approximate |
| Water spray tank | approx. 379 L (100 gal) |
| Hydraulic system | not published |
| Engine oil | not published |
| Cooling system | not published |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
PR-105 fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) | Not documented for this exact serial range — verify with your dealer or the PR-105 OMM plate. The 3204 engine commonly cited for this machine is not independently confirmed and may conflict with the unit’s actual power class. | Not documented; if 3204-era mechanical diesel is confirmed on your serial, use Cat DEO (Diesel Engine Oil), viscosity per ambient temperature per the Cat lubricant recommendations chart. |
| Cooling system | Not documented for this exact serial range — verify with your dealer. | Not documented; Cat ELC or a heavy-duty coolant/antifreeze meeting Cat's water/glycol spec is the general-line recommendation for this era of engine. |
| Fuel tank | 212 L (56.1 US gal) | No. 2-D diesel fuel, or per ambient temperature per Cat's diesel fuel recommendations. |
| Water spray system tank | 379 L (100 US gal) | Clean water for dust suppression/cutter spray; no additive specified in available sources. |
| Transmission/powertrain compartments | Not documented for this exact serial range — verify with your dealer or OMM. | Not documented; Cat TDTO (Transmission/Drive Train Oil) is the standard-line recommendation for Cat powertrain compartments of this era, viscosity per ambient temperature. |
| Final drives (each) | Not documented for this exact serial range — verify with your dealer or OMM. | Not documented; Cat TDTO is the typical final-drive fluid recommendation for Cat machines of this era. |
| Hydraulic system and tank | Not documented for this exact serial range — verify with your dealer or OMM. | Not documented; Cat HYDO (Hydraulic Oil) is the standard-line recommendation for Cat hydraulic systems of this era, viscosity per ambient temperature. |
| Grease (chassis/pivot points) | Not applicable (grease is applied per point, not a bulk-fill capacity). | Cat multipurpose grease (MPGM) or equivalent NLGI-graded lithium-complex grease, standard Cat recommendation for cold planer pivot and slide points. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Caterpillar PR-105 maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 10 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
| Every 4,000 h |
|
Servicing the PR-105 beyond the schedule
Predictive Maintenance & Fluid Analysis
The PR-105 runs a naturally aspirated Cat 3204 diesel with a fully mechanical fuel system, so there's no ECM data to trend. Build a paper trail instead: sample engine oil, hydraulic oil, and final-drive/wheel-motor oil at every scheduled change, watching for silica from cutting-drum dust ingestion and abnormal metal wear. Check air filter restriction often given the abrasive milling environment. Track coolant condition closely, since this engine has no aftercooling to mask overheating caused by a clogged radiator or slipping fan belt.
Corrective & Common Repairs
Worn or snapped cutting-drum tool holders and chipped bits are the top wear item; inspect after every shift. Hydro-mechanical wheel-drive components (chains, belts, gearboxes) loosen and wear on a machine this age, so check tension and backlash regularly. Water-spray nozzles clog with milling slurry and starve drum cooling, accelerating tool wear; clear them daily. On the 3204, injector and fuel-line leaks are common at this service life; inspect lines at every fluid service and replace deteriorating hoses proactively rather than reactively.
Overhaul & Rebuild Points
Drum bearings, seals, and tool-holder pockets are the primary rebuild targets given the abrasive-dust environment; plan a drum-housing teardown at major overhaul milestones. The 3204's mechanical fuel system and lack of aftercooling make it a straightforward top-end rebuild candidate once compression drops or blow-by increases. Wheeled final drives and steering linkages, run hard for decades, often need bushing and bearing replacement. Because this is a 1980s CMI-built machine, source rebuild parts through Cat 3204 engine channels rather than expecting dedicated PR-105 support.
Seasonal & Environment Servicing
The PR-105's open operator station and naturally aspirated 3204 have no advanced cold-weather aids, so check batteries, block heaters, and starting aids before winter work. Drain or winterize the water-spray tank and lines to prevent freeze-cracking. In hot, dusty milling conditions, service the air filter and radiator fins more often and inspect drum seals for accelerated wear from abrasive grit. Being a wheeled, non-tracked machine, also check tire pressure across seasonal temperature swings.
PR-105 fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| Low Engine Oil Pressure (warning lamp + buzzer) | Oil pressure switch on the engine block has dropped below its calibrated setpoint | Worn oil pump, plugged suction screen, low oil level, or a failed/miscalibrated pressure switch on the mechanical Cat 3204 | Shut engine down immediately, check oil level and condition, then verify actual pressure with a mechanical gauge before trusting the switch |
| High Coolant Temperature (warning lamp + buzzer) | Coolant temperature switch has exceeded its setpoint, engine may auto-shutdown depending on panel wiring | Low coolant level, plugged radiator/core, slipping or broken fan belt, faulty thermostat, or water pump failure | Idle down, confirm coolant level and belt condition once safe, inspect radiator fins and hoses before restarting |
| Low Coolant Level | Coolant level sensor in the surge tank or radiator top tank has been uncovered | External leak at hoses/water pump/core, or internal head gasket seepage | Do not add cold coolant to a hot engine; let it cool, then inspect for leaks before topping off |
| Air Filter Restriction (service indicator, mechanical gauge or lamp) | Vacuum-actuated restriction indicator shows intake filter has reached its change point | Dust-loaded primary element, common on a cold planer working in constant airborne millings dust | Replace or clean the primary air filter element and reset the restriction indicator |
| Alternator / No Charge (warning lamp) | Charging system voltage has fallen below the lamp's trip threshold | Broken or slipping alternator belt, failed alternator/regulator, or a loose/corroded battery connection | Check belt tension first, then load-test the alternator and inspect battery cable connections |
| Hydraulic Oil Temperature High (gauge/lamp) | Hydraulic reservoir temperature has exceeded the safe operating range for the drum-drive and propel circuits | Low hydraulic fluid level, plugged oil cooler fins, failing cooler fan drive, or a relief valve stuck/set wrong causing continuous high-pressure bypass | Idle down, let hydraulic oil cool, check fluid level and cooler core for debris packed in by milling dust |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
PR-105 attachments & work tools
Cutting drum / rotor
The PR-105 is a compact self-propelled cold planer from Cat's original 1985 planer lineup (built with CMI), not a carrier-mounted work tool. Documentation points to a narrow-class cutting drum around 457mm (18in) wide, fixed to the machine rather than swapped between machines.
Cutting tools (bits)
The drum uses carbide-tipped cutting bits set in bolt-on holders, the standard wear-item arrangement for Cat cold planer drums of this era. No documentation confirms optional bit styles (concrete vs asphalt) specific to this model — that distinction is documented for Cat's later compact attachment-style planers, not confirmed here.
Water spray / cooling system
Factory-fitted water spray system with roughly 379 L (100 US gal) tank capacity, used to cool cutting bits and suppress dust during milling. Documented as standard equipment on this model, not a separate add-on kit.
Engine and travel drive
Powered by a Caterpillar 3204 diesel rated around 67 kW (90 hp) gross, driving both the cutting rotor and a wheeled travel drive. Documented travel speed is about 8 km/h (5 mph); fuel capacity is approximately 212 L (56 gal).
Operator station / guarding
Sale listings describe an open operator station (canopy-type, no enclosed cab) for this model. No factory cab or ROPS enclosure option is documented for the PR-105 in available sources.
Material discharge / conveyor
No source reviewed confirms a discharge conveyor arrangement specific to the PR-105, unlike the larger PR-450 which documents a dedicated side conveyor. Given the machine's compact size and light operating weight class, material handling configuration should be verified against the actual unit or a dealer rather than assumed.
All PR-105 assemblies by section
Every catalogued assembly group for the Caterpillar PR-105. Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Pavement Profiler
413549 3 Pump Drive Gear Box, 1.27 : 1 Ratio
| 41***49 | 3 Pump Drive Gear Box | 1 |
413532 3-Pump Drive Gear Box, 1.27 : 1 Ratio
| 41***32 | 3-Pump Drive Gear Box | 1 |
7r8806 Adapter Gp-Overhung Load
| 7R***06 | Adapter Group-Overhung Load | 1 |
Assembly-Conveyor - Part 5 Of 5
Assembly-Conveyor Part 3 Of 5
Assembly-Conveyor Part 1 Of 5
Assembly-Conveyor Part 2 Of 5
Assembly-Conveyor Part 4 Of 5
Assy-Conveyor Dr. System
504482 Auxiliary Cutter Assembly
| 50***82 | Auxiliary Cutter Assembly | 1 |
5045044 Auxiliary Cutter Hyd. System
| 50***44 | Auxiliary Cutter Hydraulic. System | 1 |
5045066 Auxiliary Cutter Hydraulic System
| 50***66 | Auxiliary Cutter Hydraulic System | 1 |
8c0338 Brake As-Hydraulic
| 8C***38 | Brake As-Hydraulic | 1 |
8c0388 Clutch Gp-Hydraulic
| 8C***88 | Clutch Group-Hydraulic | 1 |
8c3907 Clutch Gp-With Brake As
| 8C***07 | Clutch Group-With Brake As | 1 |
Cmi Roto-Mill Cutting Teeth
Conveyer Attachment Group (8c5794)
| 8C***94 | Conveyer Attachment Group | 1 |
Cowling And Tanks Assembly
8t6266 Cutter As-24" Wide
| 08***17 | Housing | 1 |
| 6V***88 | Nut-Full (1/2-13 Thd); (1/2-13-Thd)(Full) | 4 |
| 7X***25 | Bolt (1/2) (63.5mm Thick) | 4 |
8t6256 Cutter As
| 8T***56 | Cutter As | 1 |
8t6260 Cutter As
| 8T***60 | Cutter As | 1 |
8t6257 Cutter As
| 8T***57 | Cutter As | 1 |
Cutter Assembly
504484 Cutter Assembly
| 50***84 | Cutter Assembly | 1 |
8t6263 Cutter Gp-18" Wide
| 6R***57 | Strap | 1 |
| 6R***58 | Housing | 1 |
| 6V***88 | Nut-Full (1/2-13 Thd); (1/2-13-Thd)(Full) | 4 |
8t6262 Cutter Gp-16"
| 8T***62 | Cutter Group-16" | 1 |
7r7862 Cylinder As-Hydraulic (Chg Lvl 04)
| 7R***62 | Cylinder As-Hydraulic | 1 |
5045050 Cylinders Hyd. System
| 50***50 | Cylinders Hydraulic. System | 1 |
5042007 Decal Group
| 50***07 | Decal Group | 1 |
5049035 Electrical Assembly
| 50***35 | Electrical Assembly | 1 |
5049025 Electrical Assembly
| 50***25 | Electrical Assembly | 1 |
5049045 Electrical Box
| 50***45 | Electrical Box | 1 |
Front Console Assembly
5045045 Fuel Line System
| 50***45 | Fuel Line System | 1 |
5045067 Fuel Line System
| 50***67 | Fuel Line System | 1 |
5045059 Grease Circuit
| 50***59 | Grease Circuit | 1 |
Group-Cutter Hsg. (18"Cutter) Part 3 Of 4
Group-Cutter Hsg. (18"Cutter) Part 4 Of 4
Group-Cutter Hsg. (18"Cutter) Part 2 Of 4
Group-Cutter Hsg. (18"Cutter) Part 1 Of 4
8t4572 Head Gp-Control
| 8T***72 | Head Group-Control | 1 |
5045046 Hyd. Oil Replenishing System
| 50***46 | Hydraulic. Oil Replenishing System | 1 |
504331 Left Front Wheel Assembly
| 50***31 | Left Front Wheel Assembly | 1 |
5045048 Maincutter Hydraulic System
| 50***48 | Maincutter Hydraulic System | 1 |
504219 Mainframe Assembly
| 50***19 | Mainframe Assembly | 1 |
8c1346 Motor Gp-Hydraulic
| 8C***46 | Motor Group-Hydraulic | 1 |
504580 Power Pack Assembly 504109 Thru 504113
| 50***80 | Power Pack Assembly | 1 |
5041503 Power Pack Assembly Beginning At 504114
| 50***03 | Power Pack Assembly | 1 |
504561 Power Pack Assy. - John Deere Engine
| 50***61 | Power Pack Assembly. - John Deere Engine | 1 |
Pr-100 & Pr-100-Dc Pavement Profiler
5045049 Pressure And Return Hydraulic System
| 50***49 | Pressure And Return Hydraulic System | 1 |
5045075 Pressure And Return Hydraulics System
| 50***75 | Pressure And Return Hydraulics System | 1 |
8c3904 Pump Gp
| 8C***04 | Pump Group | 1 |
504333 Rear Wheel Assembly
| 50***33 | Rear Wheel Assembly | 1 |
504354 Right Front Wheel Assembly
| 50***54 | Right Front Wheel Assembly | 1 |
5041216 Scales Assembly
| 50***16 | Scales Assembly | 1 |
504945 Seat And Arm Rest Assembly
| 50***45 | Seat And Arm Rest Assembly | 1 |
504953 Side Console Assembly
| 50***53 | Side Console Assembly | 1 |
504966 Side Console Assembly
| 50***66 | Side Console Assembly | 1 |
8c7633 Steering As
| 8C***33 | Steering As | 1 |
413542 Torque Hub Assembly
| 41***42 | Torque Hub Assembly | 1 |
8c3906 Torque Hub Gp
| 8C***06 | Torque Hub Group | 1 |
8t4047 Valve As-Cylinder Lock
| 8T***47 | Valve As-Cylinder Lock | 1 |
870933 Valve As-Hydraulic
| 08***33 | Valve As-Hydraulic | 1 |
5043011 Water Spray Assembly
| 50***11 | Water Spray Assembly | 1 |
Water Spray Assembly
| 50***14 | Water Spray Assembly | 1 |
5045047 Wheel Drive Hyd. System
| 50***47 | Wheel Drive Hydraulic. System | 1 |
5045073 Wheel Drive Hydraulic System
| 50***73 | Wheel Drive Hydraulic System | 1 |
5045074 Wheel Drive Hydraulic System
| 50***74 | Wheel Drive Hydraulic System | 1 |
5045072 Wheel Drive Hydraulic System
| 50***72 | Wheel Drive Hydraulic System | 1 |
8c0294 Wheel Gp-Steering
| 03***59 | Hose Assem. 12 In. (3.05 Dm) | 2 |
| 03***84 | Union-Flared | 1 |
| 06***57 | Elbow-Flared | 1 |
PR-105 serial number reference
On this generation of machine (mid-1980s, pre-2001 numbering) the ID plate is a simple serial tag, not the later 17-character PIN. It is usually riveted to the main frame near the operator's platform or on the engine compartment sill, stamped with the 3-letter prefix followed by the running serial digits (e.g. 5WC00123). Read the first three letters as the prefix that ties the unit to its parts/service manual family, and the digits after it as the individual unit's sequence number.
| Prefix | Identifies | Notes |
|---|---|---|
| 5WC | PR-105 pavement profiler (cold planer), shared serial range with sibling PR-100 and PR-100DC configurations of the same base machine | Serial range 5WC00001-up. This is the only prefix documented for the PR-105 in parts and service literature; the same range covers the PR-100 and PR-100DC variants rather than a separate prefix per variant. Machine dates to Caterpillar's mid-1980s Pavement Profiler line (CMI Roto-Mill lineage) alongside the PR-75, PR-450, PR-750 and PR-1000, each of which carries its own distinct prefix (PR-75 is 6BD, PR-450 is 7DC) - do not borrow those numbers onto the PR-105. Engine model, plant, and narrower sub-range splits are not confirmed from independent literature; verify with your dealer if pinning down build year or powerplant. |
Frequently asked questions
What engine does the Caterpillar PR-105 use?
A naturally aspirated Caterpillar 3204 diesel, rated at roughly 89.9 hp (67 kW) gross.
What is the operating weight of the PR-105?
Approximately 7,710 kg (17,000 lb), typical for this class of wheeled pavement profiler.
What replaced the Caterpillar PR-105?
There's no single documented direct successor. Caterpillar phased out the CMI-built PR-series as it moved cold-planer production onto its own PM-series machines with tracked undercarriages and electronic controls. Treat any specific successor claim as unconfirmed and verify with a dealer.
What PR-105 owners discuss
What's the reputation of the 3204 engine in the PR-105 among owners and mechanics?
What wear patterns show up on the running gear, since this profiler rides on wheels rather than tracks?
What's the biggest source of wear inside the cutting drum and housing?
What maintenance issues come up with the water spray system and discharge conveyor?
What electrical or gauge problems typically show up on a machine this old?
How does the hydraulic drum drive behave, and what do owners watch for?
What should you check when buying a used PR-105?
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
Need a specific PR-105 part?
Search live OEM part data, check fitment, and cross-reference alternatives with Heavy Parts AI.