Caterpillar 325C L
Maintenance schedule, common problems & OEM parts breakdown
The Cat 325C L is a medium hydraulic excavator in the third generation of Caterpillar's 325-series crawler excavator line, sitting in the 27-29 tonne class. It runs the Cat 3126B ATAAC diesel, a turbocharged, air-to-air aftercooled 7.2 L inline-six with HEUI (hydraulically actuated, electronically controlled unit injection) fuel delivery, rated at roughly 140 kW (188 hp) net and meeting Tier 2 emissions. Operating weight falls in a 27,500-28,600 kg (60,700-63,052 lb) band depending on boom, stick, and counterweight configuration. Production ran roughly 1999/2000 through 2005, following the Tier 1-era 325B/325B L (mechanically governed 3306 engine) and preceding the 325D/325D L, which used Cat's C7 ACERT engine. Cat built the C-series platform in several configurations sharing the same chassis and engine: the standard L long-undercarriage version, LN narrow-gauge, CR compact/short-radius swing, MH material handler, and wheeled M-325C variants.
The move from 325B to 325C replaced the mechanically governed 3306 engine with the electronically managed, HEUI-injected 3126B, improving fuel economy, cold-start behavior, and diagnostics through Cat Electronic Technician while stretching service intervals to cut downtime versus the B-series. Hydraulic and swing-system updates also improved cycle times over the B-series, though the following 325D L pushed output and productivity further with its C7 ACERT engine. In today's used and parts market, the 325C L sits in a practical middle ground: HEUI-era Cat 3100-series engines are well understood by independent shops, parts commonality with the highway-truck 3126/3126B keeps components available, and the simpler pre-ACERT electronics make it a common pick for buyers prioritizing lower acquisition cost and easier field service over later Tier 3/4 machines. Its long production run and shared engine platform also support a healthy secondary market for undercarriage, hydraulic, and engine parts.
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 325C L specifications
Engine
| Engine model | Cat 3126B ATAAC diesel, HEUI electronic unit injection, turbocharged and air-to-air aftercooled, inline 6-cylinder |
| Net power (ISO 9249 / EEC 80/1269) | 140 kW (188 hp) |
| Net power (SAE J1349:2011) | 139 kW (186 hp) |
| Displacement | 7.2 L (440 in³) |
| Bore x stroke | 110 mm x 127 mm (4.33 in x 5.00 in) |
| Emissions tier | Meets Tier 2 worldwide emissions requirements |
Weights
| Operating weight, standard long undercarriage (800 mm shoes) | 28,600 kg (63,052 lb) per Cat's technical spec database. Some third-party listings show 27,533 kg (60,700 lb); operating weight varies by boom/stick/bucket combination |
Dimensions
| Shipping (transport) length | 9720-10,340 mm (31'11"-33'11"), varies by boom/stick. Reach boom (6.15 m) with either stick: 10,340 mm. Mass boom (5.55 m): 9720 mm with 3.2 m stick, 9780 mm with 2.5 m stick |
| Shipping (transport) height | 3260-3400 mm (10'8"-11'2"), varies by boom/stick configuration |
| Shipping (transport) width, long undercarriage | 3390 mm (11'1") with 800 mm standard triple-grouser shoes; 3290 mm (10'10") with optional 700 mm shoes |
| Tail swing radius | 3050 mm (10'0"), same across all boom/stick configurations |
| Track shoe width | 800 mm (32") triple-grouser standard on long undercarriage; 700 mm (28") optional |
| Ground clearance | 480 mm (1'7") |
| Undercarriage length, center of rollers, long undercarriage | 3800 mm (12'6") |
| Track length on ground, long undercarriage | 4660 mm (15'3") |
| Track gauge, long undercarriage | 2590 mm (8'6") |
Performance
| Maximum digging depth | 6010-7090 mm (19'9"-23'3"). 7090 mm with 6.15 m boom and 3.2 m stick, down to 6010 mm with 5.55 m boom and 2.5 m stick |
| Maximum reach at ground level | 9340-10,510 mm (30'8"-34'6"), varies by boom/stick configuration |
| Maximum cutting height | 9230-9950 mm (30'3"-32'8"), varies by boom/stick configuration |
| Maximum loading (dump) height | 6090-7110 mm (20'0"-23'4"), varies by boom/stick configuration |
| Swing speed | 10.2 rpm |
| Maximum travel speed | 5.3 km/h (3.3 mph) |
| Maximum drawbar pull | 244 kN (54,853 lb) |
Forces
| Bucket digging force, power buckets (ISO 6015) | 183 kN (41,100 lb) with standard 3.2 m stick, up to 224 kN (50,400 lb) with the shorter 2.5 m mass-boom stick; 181 kN (40,800 lb) with the 2.65 m reach stick |
| Bucket digging force, power buckets (SAE) | 161 kN (36,200 lb) with standard 3.2 m stick, up to 199 kN (44,600 lb) with the shorter 2.5 m mass-boom stick |
| Stick (arm) digging force, power buckets (ISO 6015) | 120 kN (27,000 lb) with 3.2 m stick, up to 145 kN (32,600 lb) with the shorter 2.5 m mass-boom stick; 138 kN (31,100 lb) with the 2.65 m reach stick |
| Stick (arm) digging force, power buckets (SAE) | 116 kN (26,200 lb) with 3.2 m stick, up to 140 kN (31,500 lb) with the shorter 2.5 m mass-boom stick |
| Bucket/stick force, HD and HDR buckets vs general purpose buckets | HD and HDR buckets rate slightly under power buckets: bucket force 145-202 kN (32,500-45,500 lb ISO). General purpose buckets rate lowest: bucket force 133-184 kN (29,900-41,400 lb ISO), stick force 111-137 kN (24,900-30,700 lb ISO) |
Service capacities (summary)
| Fuel tank | 500 L (132 gal US) |
| Hydraulic system, including tank | 310 L (82 gal US) |
| Engine oil | 34 L (9 gal US) |
| Cooling system | 30 L (7.9 gal US) |
| Swing drive | 10 L (2.6 gal US) |
| Final drive, each | 6 L (1.6 gal US) |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
325C L fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) | 34 L (9.0 US gal) | Cat DEO-ULS or Cat DEO diesel engine oil, API CI-4/CI-4 PLUS or CJ-4. SAE 15W-40 for -10°C to 50°C (14°F to 122°F). SAE 10W-30 down to -18°C (0°F). SAE 0W-40 or 5W-40 synthetic for cold-soak starts below -30°C (-22°F). |
| Cooling system | 30 L (7.9 US gal) | Cat ELC (Extended Life Coolant) preferred, 12,000-hour/6-year service life. Cat DEAC (conventional heavy-duty coolant) acceptable with periodic SCA top-up. This engine uses air-to-air aftercooling: minimum 30% glycol required, 50% glycol recommended. A 50/50 mix protects to about -37°C (-34°F). Do not run water alone, or water with SCA/ELI only, on this engine. |
| Fuel tank | 500 L (132 US gal) | ULSD or LSD distillate diesel fuel meeting Cat's distillate fuel specification, minimum cetane number 40. Biodiesel blends up to B20 are acceptable per Cat guidance for this engine family. |
| Hydraulic system (total, including tank) | 310 L (82 US gal) | Cat HYDO Advanced preferred. SAE 10W below 40°C (104°F), SAE 20W for -5°C to 45°C (23°F to 113°F), SAE 30 above 10°C (50°F). Cat Bio HYDO Advanced where a biodegradable fluid is specified. Cat TDTO or TDTO-TMS is second choice. |
| Hydraulic tank | 145 L (38 US gal) | Same Cat HYDO Advanced fluid and viscosity bands as the total hydraulic system above. |
| Swing drive | 10 L (2.6 US gal) | Cat TDTO. SAE 30 is the factory-fill viscosity for moderate climates. SAE 10W below 0°C (32°F), SAE 50 above 32°C (90°F). Cat TDTO-TMS multigrade covers a wider seasonal band, roughly -25°C to 25°C (-13°F to 77°F). |
| Final drive (each) | 6 L (1.6 US gal) | Same Cat TDTO grade and viscosity guidance as the swing drive: SAE 30 factory fill, SAE 10W cold, SAE 50 hot, TDTO-TMS for wide seasonal swings. |
| Pilot/other hydraulic circuits | Not itemized separately in the factory refill table | Pilot and auxiliary control circuits draw from the main hydraulic reservoir and run the same Cat HYDO Advanced fluid as the main hydraulic system; no separate pilot-circuit fill figure is published. |
| Grease (spec only) | No factory total-fill figure; service per grease-point interval | Cat Prime Application Grease NLGI 2 is standard for boom/stick pins, bucket linkage, swing bearing, and swing gear teeth on this class of excavator. Cat Extreme Application Grease NLGI 1-2 (moly-fortified) suits continuous heavy digging duty. Cat Utility Grease NLGI 2 suits light-duty use. Swing gear and swing bearing need a tacky grease that clings to the vertical gear face. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Caterpillar 325C L maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 50 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
| Every 6,000 h |
|
Servicing the 325C L beyond the schedule
Predictive Maintenance & Fluid Analysis
Pull S·O·S samples on engine oil, hydraulic oil, swing drive, and final drive oil at every service interval. The 3126B's HEUI injection system is sensitive to fuel and hydraulic contamination, so trending wear metals catches injector or pump wear before it becomes a failure. Watch hydraulic oil cleanliness closely — the 310 L system feeds the main pump, swing motor, and travel motors, so particulate spreads fast. Track coolant condition too; ELC breakdown accelerates cylinder liner and water pump wear on this engine.
Corrective & Common Repairs
Track and swing seals, HEUI injector wiring, and travel motor drift are the recurring complaints on high-hour 325C L machines. Injector harness chafe against the valve cover or turbo heat shield causes misfires and hard starts — inspect routing at every oil change. Swing bearing backlash and gear wear show up as play during rotation; check clearance before condemning the whole bearing. Final drive seal leaks and travel motor drift are common past 8,000 hours and usually trace to worn motor seals, not the pump.
Overhaul & Rebuild Points
Major rebuild points on the 325C L are the 3126B's HEUI injectors and turbocharger, the main hydraulic pump, and the undercarriage. Injectors and turbo typically need attention around 8,000-12,000 hours depending on fuel quality; watch for smoke, power loss, or rough idle as early flags. The variable-displacement main pump and swing motor wear gradually — cycle time loss and hunting under load signal a teardown is due. Undercarriage (chains, rollers, idlers, sprockets) is usually the first major wear item, often needing replacement before the engine or hydraulics do.
Seasonal & Environment Servicing
Cold-climate starts stress the HEUI system — verify fuel heater and cold-start aid function before winter, and keep the 500 L fuel tank topped up to limit condensation. Switch to correct-viscosity engine oil and check ELC freeze protection before temperatures drop. On hot, dusty sites, clean the air filter and hydraulic oil cooler fins more often than the standard interval, and check the cab A/C condenser for clogging. Wet or abrasive ground accelerates undercarriage and final drive seal wear, so shorten track inspection intervals in those conditions.
325C L fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| 164-11 | Injection actuation (HEUI) pressure system fault - ECM is not seeing the commanded injection actuation oil pressure. | Failed injection actuation pressure control valve, faulty injection actuation pressure sensor, low or contaminated engine oil (doubles as HEUI hydraulic fluid), or worn high-pressure oil pump. | Check engine oil level and condition first, then verify sensor and control-valve wiring before replacing either part. |
| 190-08 / 342-08 | Primary (CID 190) or secondary (CID 342) engine speed/timing sensor signal abnormal. | Worn sensor tip, incorrect sensor-to-gear air gap, chafed harness near the sensor bracket, or a failed sensor; the dual-sensor design lets the engine keep running on the remaining good sensor until it also degrades. | Check sensor air gap and connector condition; a hard no-start with no stored code can still trace back to a marginal speed/timing sensor, so inspect or replace the pair as a set. |
| 100-03 / 100-04 | Engine oil pressure sensor circuit voltage above normal (03) or below normal (04). | Open or shorted wiring at the oil pressure sensor connector, corroded pins, or a failed sensor. | Inspect the sensor connector and harness for damage or moisture before replacing the sensor. |
| 110-03 / 110-04 | Engine coolant temperature sensor circuit voltage above normal (03) or below normal (04). | Open or short in the coolant temperature sensor wiring, or a failed sensor; the ECM also uses this input for cold-start and injection pressure strategy, so a bad reading can cause hard starting or rough running. | Check sensor wiring and connector first; replace the sensor if the circuit tests good but the reading stays implausible. |
| 105-03 / 105-04 | Inlet manifold air temperature sensor circuit open (03) or short (04). | Damaged sensor wiring or connector on the intake manifold, or a failed sensor. | Pull-test the harness pins at the sensor and ECM connector, repair as needed, then retest before replacing the sensor. |
| 168-00 / 168-01 | Electrical system (battery) voltage above (00) or below (01) the ECM's normal operating range. | Weak or failing battery, poor ground or connection, or a charging system fault. | Load-test the batteries and check charging voltage and ground straps before chasing the ECM. |
| 262-03 / 262-04 | 5-volt sensor supply circuit voltage above (03) or below (04) normal; this supply feeds several engine sensors, so one fault here can trigger multiple other sensor codes at once. | Shorted or open sensor supply wiring, or a shorted sensor sharing that supply circuit. | Disconnect sensors on the shared 5V supply one at a time to isolate the shorted circuit before replacing parts. |
| 1-05/06 through 6-05/06 | Individual cylinder injector solenoid circuit open (current below normal) or shorted (current above normal); the CID number (1-6) identifies the affected cylinder. | Damaged injector wiring harness or connector, or a failed injector solenoid. | Check harness routing and connector condition at the affected cylinder before replacing the injector. |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
325C L attachments & work tools
Buckets
Factory reach-boom setup ships with an HD bucket rated 0.9 m³ (1.18 yd³) on the standard R2.9 m stick. C-family buckets (Reach Boom, shorter sticks) and D-family buckets (Mass Boom, longer sticks) span roughly 0.9-1.7 m³ (1.18-2.2 yd³) across General Purpose, Ditch Cleaning, Heavy-Duty, Heavy-Duty Rock and Heavy-Duty Power classes; exact capacity varies by stick/boom pairing and duty class. Buckets mount pin-on as standard, with a pin-grabber quick coupler (about 90 mm / 3.5 in pin diameter) available for tool-less swaps.
Hydraulic hammers
Operating weight on this machine (roughly 27.5-29.5 t depending on undercarriage and counterweight) sits in the 25-30 t carrier class. That matches the medium-duty performance hammer range built for 320-330-size carriers, service-weight class around 1,700-2,400 kg (3,740-5,245 lb). Comparable-class breakers from other hammer brands are sized to the same 25-30 t carrier range; match hammer to the machine's actual configured operating weight, not nameplate class alone.
Quick couplers
Factory pin-grabber quick coupler uses the linkage common to the 320-325 excavator class, around 90 mm (3.5 in) pin diameter. Locking is a redundant primary-wedge-plus-secondary-latch design. Hydraulically actuated couplers are typical for fast tool changes on this class; plain pin-on mounting is still used when no coupler is fitted.
Thumbs/grapples
Stick ships thumb-ready with the quick-coupler hydraulic circuit pre-installed, so no extra plumbing is needed to add a thumb. Both hydraulic (powered, adjustable-grip) and mechanical (bolt-on, fixed-pivot) thumbs fit this class. Hydraulic and rotating hydraulic grapples, including orange-peel style for scrap and bulk material handling, run off the same attachment hydraulic circuit.
Rippers
Single-shank rippers sized for the 320-325 excavator class fit this machine, mounted in place of or alongside the bucket linkage, for breaking hard or frozen ground and undercutting rock ahead of digging. Not a factory-catalog work tool on this model; sourced through attachment suppliers building to the 320-325 pin and linkage pattern.
Hydraulic-kit notes
The C-series attachment hydraulic system on this platform runs a factory-installed medium-pressure auxiliary circuit for hammer, thumb and shear-type tools, plus a two-pump combined-flow (high-flow) circuit for tools that need more flow, such as grapples or processors. Base machine main pump flow runs about 235 L/min (62 gpm) at roughly 34,300 kPa (4,974 psi) system relief. An optional Tool Control System lets the operator match flow, pressure and controls to the mounted tool with preprogrammed settings.
All 325C L assemblies by section
Every catalogued assembly group for the Caterpillar 325C L. Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Electrical And Starting System
2184377 Wiring Gp-Battery &
| 21***77 | Battery & Wiring Group | 1 |
1114688 Lighting Gp
| 11***88 | Lighting Group-Boom; -Long | 1 |
2227905 Wiring Gp-Cab Riser
| 22***05 | Wiring Group-Cab Riser; (Cab Raiser) | 1 |
2227906 Wiring Gp-Cab Riser
| 22***06 | Wiring Group-Chassis | 1 |
2224426 Wiring Gp-Console (Rh)
| 22***26 | Wiring Group-Console; (Console) (Rh) | 1 |
1706909 Wiring Gp-Console (Lh)
| 17***09 | Wiring Group-Console; (Lh) | 1 |
2202152 Wiring Gp-Console
| 17***09 | Wiring Group-Console; (Lh) | 1 |
| 22***52 | Wiring Group-Console; (Console) | 1 |
| 22***26 | Wiring Group-Console; (Console) (Rh) | 1 |
2224433 Wiring Gp
| 22***33 | Wiring Group-Material Handler | 1 |
Frame And Body
2318962 Counterweight Gp
| 23***62 | Counterweight & Mounting Group | 1 |
2371030 Frame Gp-Upper
| 23***30 | Frame Group-Upper; (Upper) | 1 |
1994529 Gear & Bearing Gp
| 19***29 | Gear & Bearing Group-Swing | 1 |
2238882 Guard Gp-Bottom
| 22***82 | Guard Group-Bottom; (Bottom) | 1 |
2296703 Guard Gp-Swivel
| 22***03 | Guard Group-Swivel; (Swivel) | 1 |
2244518 Ladder Gp
| 22***18 | Ladder Group | 1 |
2240789 Mounting Gp-Cab
| 22***89 | Mounting Group-Cab; (Cab) | 1 |
Hydraulic System
2181104 Lines Gp-Pilot
| 21***04 | Control Group-Pilot Operated Hydraulic | 1 |
2231472 Cylinder Gp-Lines (Rh)
| 22***72 | Cylinder & Lines Group-Boom; -Rh | 1 |
2231471 Cylinder Gp-Lines (Lh)
| 22***71 | Cylinder & Lines Group-Boom; -Lh | 1 |
2033927 Cyl Gp-Seal&
| 20***27 | Cylinder & Seal Group-Boom | 1 |
2138200 Cyl Gp-Seal&
| 21***00 | Cylinder & Seal Group-Stick | 1 |
2033906 Cylinder Gp-Boom
| 20***06 | Cylinder Group-Boom | 1 |
2536503 Cylinder Gp-Stick
| 25***03 | Cylinder Group-Stick; (Stick) | 1 |
2141591 Cylinder Gp-Boom
| 21***91 | Cylinder Group-Stick | 1 |
2074558 Guard Gp-Stick
| 20***58 | Guard Group-Cylinder; -Stick | 1 |
2181111 Lines Gp-Auxiliary Hydraulic
| 21***11 | Lines Group-Auxiliary Hydraulic | 1 |
2153213 Lines Gp-Boom
| 21***13 | Lines Group-Boom | 1 |
2138201 Lines Gp-Boom
| 21***01 | Lines Group-Boom; (Boom) | 1 |
2181102 Lines Gp-Front
| 21***02 | Lines Group-Front; (Front) | 1 |
2180971 Lines Gp-Riser
| 21***71 | Lines Group-Hydraulic; -Cab Riser | 1 |
2138210 Lines Gp-Pilot
| 21***10 | Lines Group-Pilot; -Stick Lowering Control | 1 |
2181106 Lines Gp-Pilot
| 21***06 | Lines Group-Pilot | 1 |
2181110 Lines Gp-Pilot
| 21***10 | Lines Group-Pilot | 1 |
2181105 Lines Gp-Pilot
| 21***05 | Lines Group-Pilot | 1 |
2181107 Lines Gp-Pilot
| 21***07 | Lines Group-Pilot | 1 |
2215041 Lines Gp-Pump
| 22***41 | Lines Group-Pump; (Pump) | 1 |
2181109 Lines Gp-Return
| 21***09 | Lines Group-Return | 1 |
2181108 Lines Gp-Return
| 21***08 | Lines Group-Return | 1 |
2181103 Lines Gp-Return & Filter
| 21***03 | Lines Group-Return & Filter | 1 |
2138207 Lines Gp-Stick
| 21***07 | Lines Group-Stick; (Stick) | 1 |
2138205 Lines Gp-Stick
| 21***05 | Lines Group-Stick; -Grapple Rotate | 1 |
2180969 Lines Gp-Travel Motor
| 21***69 | Lines Group-Travel Motor | 1 |
2174621 Mounting Gp-Valve
| 21***21 | Mounting Group-Main Control Valve | 1 |
2103030 Pump Gp-Mounting &
| 21***30 | Pump & Mtg Group-Auxiliary | 1 |
2167936 Valve Gp-Control
| 21***36 | Valve Group-Main Control | 1 |
Implements
2183398 Boom Gp
| 21***98 | Boom Group | 1 |
2225436 Lines Gp-Grease
| 22***36 | Lines Group-Grease; -Boom | 1 |
2138204 Lines Gp-Grease
| 21***04 | Lines Group-Grease; -Stick | 1 |
2126467 Stick Gp
| 21***67 | Stick Group | 1 |
Machine Arrangement
2190114 Merchandise Ar
| 11***88 | Lighting Group-Boom; -Long | 1 |
| 18***13 | Guard Group-Travel Motor; -Heavy-Duty | 1 |
| 18***40 | Track Group; -600-mm (23.62-In) Triple Grouser Shoe | 2 |
2532760 Merchandise Ar
| 21***14 | Merchandise Ar | 1 |
| 23***89 | Mounting Group-Magnet | 1 |
| 25***60 | Merchandise Ar | 1 |
Operator Station
2371033 Cab Gp
| 23***33 | Cab Group | 1 |
2371060 Guard Gp-Overhead
| 23***60 | Guard Group-Overhead | 1 |
2238876 Lines Gp-Air Conditioner
| 22***76 | Lines Group-Air Conditioner | 1 |
2214046 Lines Gp-Washer
| 22***46 | Lines Group-Window Washer; -Fixed Cab Riser | 1 |
1963296 Platform Gp-Operator
| 19***96 | Platform Group; (Operator) | 1 |
2202156 Riser Gp
| 22***56 | Riser Group-Cab; (Cab) | 1 |
2191729 Washer Gp-Windshield
| 21***29 | Washer Group-Window | 1 |
2242679 Wiper Gp-Window
| 22***79 | Wiper Group-Window; (Window) | 1 |
Power Train
2276138 Drive Gp-Final
| 22***38 | Final Drive Group; -With Motor | 1 |
Service Equipment And Supplies
2184369 Lubricant Gp
| 10***73 | Film-Stripe; (Accent Red)(800-cm) | 0 |
| 10***45 | Film-Identification; (Cat) | 2 |
| 12***29 | Film; (Accum, High Press, Read Omm) | 1 |
Undercarriage
2144264 Frame As-Undcrg
| 21***64 | Frame As-Undcrg | 1 |
1845713 Guard Gp-Track Motor
| 18***13 | Guard Group-Travel Motor; -Heavy-Duty | 1 |
2319372 Idler Gp-Front
| 23***72 | Idler Group-Front | 1 |
2202328 Roller Ar-Hd
| 22***28 | Roller Ar-Track & Carrier | 1 |
1883240 Track Gp
| 18***40 | Track Group; -600-mm (23.62-In) Triple Grouser Shoe | 1 |
325C L serial number reference
The PIN/serial number plate is mounted on the right-hand exterior of the operator's cab, below the cab window (older units may also carry a duplicate plate on the frame near the cab base). Read the first three characters as the serial-number prefix, identifying the specific production/parts-book break, followed by a five-digit sequence number within that break. Machines built before 2001 show an 8-character serial (3-letter prefix plus 5-digit sequence); 2001-and-later machines carry the full 17-character PIN using the same prefix-plus-sequence logic.
| Prefix | Identifies | Notes |
|---|---|---|
| AMH | 325C / 325C L combined-prefix range | Serial prefix range for 325C and 325C L excavators, powered by the Cat 3126B engine. |
| JLC | 325C / 325C L combined-prefix range | Serial prefix range for 325C and 325C L excavators, powered by the Cat 3126B engine. |
| JLD | 325C / 325C L combined-prefix range | Serial prefix range for 325C and 325C L excavators, powered by the Cat 3126B engine. |
| BTD | 325C / 325C L combined-prefix range | Serial prefix range for 325C and 325C L excavators, powered by the Cat 3126B engine. |
| BFE | 325C / 325C L combined-prefix range | Serial prefix range for 325C and 325C L excavators, powered by the Cat 3126B engine. |
| BKW | 325C / 325C L combined-prefix range | Frame-and-body and machine documentation for this range covers both 325C and 325C L, powered by the Cat 3126B engine. |
| CRB | 325C L / 325C LN combined-prefix range | Hydraulic system and machine documentation for this range covers both 325C L and 325C LN (narrow/long-undercarriage variant), powered by the Cat 3126B engine. |
Frequently asked questions
What engine does the Caterpillar 325C L use?
The 325C L is powered by the Cat 3126B ATAAC diesel, a 7.2 L HEUI-injected, turbocharged and air-to-air aftercooled inline-six rated at roughly 140 kW (188 hp) net, meeting Tier 2 emissions standards.
What is the operating weight of the Caterpillar 325C L?
Operating weight runs approximately 27,500-28,600 kg (60,700-63,052 lb) depending on boom/stick length and counterweight configuration. Check the specific machine configuration for an exact figure.
What replaced the Caterpillar 325C L?
The Cat 325D and 325D L replaced the 325C L around 2005-2006. The D-series switched to the electronically controlled C7 ACERT engine (152 kW/204 hp net), met Tier 3 emissions, and carried updated hydraulics and longer service intervals over the C-series.
What 325C L owners discuss
What powertrain or hydraulic quirks do owners bring up most often for the 325C L?
What wear patterns show up in the undercarriage and final drives?
What engine quirks are specific to the 3126B ATAAC used in the 325C L?
What electrical or sensor issues come up most in owner discussions?
Are any reported hydraulic-control issues safety-critical?
What should a buyer check on a used 325C L before purchase?
How do owners and mechanics generally rate the 325C L's reliability?
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
Need a specific 325C L part?
Search live OEM part data, check fitment, and cross-reference alternatives with Heavy Parts AI.