Caterpillarexcavator

Caterpillar 329E LN

Maintenance schedule, common problems & OEM parts breakdown

The Cat 329E LN is a roughly 29-31 tonne class (63,300-69,750 lb) crawler excavator built on the long-narrow-gauge undercarriage, a reduced-width track frame aimed at confined job sites compared with the standard-gauge 329E L. It runs the Cat C7.1 ACERT six-cylinder turbocharged diesel, rated 161 kW (216 hp) net flywheel power and roughly 179-181 kW (241-243 hp) gross depending on which rating standard the factory sheet uses, meeting U.S. EPA Tier 4 Interim and EU Stage IIIB emissions through the Cat Clean Emissions Module rather than a DEF-based system. Caterpillar built the E-series 329 line from around 2011 through 2019, offering the 329E LN alongside the base 329E and long-undercarriage 329E L, with boom, stick, counterweight, and 600/700/800 mm shoe combinations spanning operating weight from about 28.7 t up to 31.6 t. It followed the C6.6 ACERT-powered 329D/329D L/329D LN generation and was itself succeeded by the Tier 4 Final 329F series.

The move from D-series to E-series swapped the 329's C6.6 ACERT engine for the larger-displacement C7.1 ACERT and added the Clean Emissions Module for particulate control, along with updated hydraulics and cab electronics; the later F-series then layered Tier 4 Final aftertreatment on top of that. Within the E-series itself, the LN's narrower undercarriage trades a bit of stability and lower ground pressure for a smaller transport and working footprint, which is why utility, road, and urban contractors favor it over the L. In the used and parts market today, the 329E LN sits in a well-supported window: enough units were built and are now aging past their first major overhaul that undercarriage, swing, and hydraulic component demand stays steady, while shared service documentation with the 329E L keeps most parts and repair procedures common between the two configurations.

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 329E LN specifications

Engine

Engine model	Cat C7.1 ACERT, 6-cylinder turbocharged diesel
Bore x stroke	105 mm x 135 mm (4.13 in x 5.31 in)
Displacement	7.01 L (428 cu in)
Gross power	179-180 kW (241-243 hp), figure varies slightly by rating standard (SAE J1995 vs ISO 14396) used across factory sheets
Net flywheel power	161 kW (216 hp)
Emissions tier	Meets U.S. EPA Tier 4 Interim and EU Stage IIIB

Weights

Operating weight range	28 717-31 639 kg (63,310-69,750 lb) across boom/stick/counterweight/shoe combinations; long-narrow (LN) undercarriage sits near the middle of this band, around 29.5 t
Ground pressure, long undercarriage (L)	41.2-59.7 kPa (6.0-8.7 psi) depending on shoe width (600-800 mm) and boom/stick combination, with 800 mm shoes at the low end
Ground pressure, long-narrow undercarriage (LN)	Runs higher than L at a given shoe width due to the narrower track gauge, around 46 kPa (6.7 psi) on 600 mm shoes; exact figure varies by boom/stick/counterweight configuration
Transport weight	Matches the minimum operating weight configuration, about 28 717 kg (63,310 lb) with HD reach boom, short stick, 5.8 t counterweight and narrower shoes

Dimensions

Transport length	9830-10 400 mm (32'3"-34'1") depending on stick; 10 386 mm (34'1") with the standard HD reach boom and long stick
Transport width, long undercarriage	3190 mm (600 mm shoes) to 3390 mm (800 mm shoes); LN undercarriage transport width runs narrower due to its reduced track gauge
Transport height	3372-3520 mm (11'1"-11'7") depending on stick, including shoe lug height
Tail swing radius	3044 mm (10'0")
Track shoe width	600 mm, 700 mm, or 800 mm (24", 28", 32") triple grouser options
Ground clearance	490 mm (1'7")
Undercarriage track length on ground	4855 mm (15'11"); length to center of rollers 3994 mm (13'1")
Track gauge	2590 mm (8'6") on the long (L) undercarriage; the long-narrow (LN) undercarriage uses a reduced gauge to cut transport width for tight job sites

Performance

Maximum digging depth	6100-7250 mm (20'0"-23'9") with standard HD reach or mass booms depending on stick; a super long reach boom/stick option extends this to about 14 750 mm (48'5")
Maximum reach at ground level	9430-10 680 mm (30'11"-35'0") with standard booms; super long reach option extends to about 18 420 mm (60'5")
Maximum cutting height	9130-10 010 mm (29'11"-32'10") with standard booms; super long reach option extends to about 13 620 mm (44'8")
Maximum loading/dump height	6000-6950 mm (19'8"-22'10") with standard booms
Swing speed	9.8 rpm; swing torque 82.2 kN-m
Maximum travel speed	5.1 km/h (3.2 mph)
Maximum drawbar pull	247-249 kN (55,500-56,000 lbf)
Gradeability	Not published in available factory spec sheets for this model

Forces

Bucket digging force (ISO, heavy duty)	179 kN with the standard HD reach boom and CB-family bucket; up to 210 kN with the mass boom and DB-family bucket. Figures vary by boom/stick and bucket family, and by rating standard (ISO vs SAE) used on different factory sheets
Stick digging force (ISO, heavy duty)	126 kN with the shorter HD reach stick, up to 152 kN with the mass boom stick; longer sticks trade digging force for reach, so figures vary by stick length and duty class (general/heavy/severe duty)

Service capacities (summary)

Fuel tank	520 L (137.4 gal)
Hydraulic system, including tank	310 L (81.9 gal); hydraulic tank alone 155 L (41.0 gal)
Engine oil, with filter	22.5 L (5.9 gal)
Cooling system	44 L (11.6 gal)

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

329E LN fluids & capacities

System	Capacity	Recommended fluid
Engine crankcase (with filter)	22.5-22.7 L (6.0 US gal)	Cat DEO-ULS ultra-low-sulfur diesel engine oil, required for this Tier 4 Interim/Stage IIIB engine with exhaust aftertreatment. SAE 10W-30 covers most ambient ranges; use 0W-40 or 5W-40 in cold climates below about -20C, and 15W-40 in consistently hot climates. Cat DEO is the fallback where ULS oil is unavailable and aftertreatment allows it.
Cooling system	44-44.3 L (11.7 US gal)	Cat ELC (Extended Life Coolant), premix or concentrate mixed to roughly 50/50 (up to 60/40 for extreme cold). Supports extended drain intervals with the ELC Extender treatment. Cat DEAC conventional coolant is the fallback on a shorter change interval.
Fuel tank	520 L (137.4 US gal)	Ultra-low-sulfur No. 2 diesel. Biodiesel blends up to B20 (meeting ASTM D6751 or EN 14214) are permitted through the machine's three-layer fuel hose and electronic high-pressure fuel system.
Hydraulic system total and hydraulic tank	System total 310 L (81.9 US gal); hydraulic tank 155 L (40.9 US gal)	Cat HYDO Advanced multigrade hydraulic oil, graded by climate: HYDO Advanced 10 for cold-to-moderate conditions (about -20C to 40C), HYDO Advanced 20 for -5C to 45C, HYDO Advanced 30 for consistently hot climates above 10C up to 50C. Cat BIO HYDO Advanced is offered as a biodegradable alternative.
Final drive (each)	6 L (1.6 US gal)	Cat TDTO (Transmission/Drive Train Oil), TO-4 specification. Monograde SAE 30 or SAE 50 selected by ambient temperature, or Cat TDTO-TMS multigrade synthetic for wide-range coverage (about -20C to 40C) without seasonal oil changes.
Swing drive	10-10.2 L (2.7 US gal)	Cat TDTO (TO-4 spec), same monograde SAE 30/50 by climate or Cat TDTO-TMS multigrade synthetic as used in the final drives.
Pilot/other circuits	Not listed as a separate compartment; pilot and servo circuits draw from the main hydraulic tank/system above	Same Cat HYDO Advanced fluid as the main hydraulic system
Grease (spec only)	No reservoir capacity; applied at boom, stick, bucket, and swing-bearing pin/bushing lube points per service interval	Cat Advanced 3Moly Grease, NLGI 2 moly-fortified EP grease. Cat XTLife Moly Grease is the extended-service alternative for longer regrease intervals.

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

Caterpillar 329E LN maintenance schedule

Service interval	Tasks
Every 10 h	Check engine oil, coolant, and hydraulic oil levels before starting. Walk around the machine and inspect for hydraulic leaks, loose fasteners, and damaged hoses on the boom/stick/bucket linkage. Drain the fuel water separator and check the fuel filter restriction indicator. Clear mud and debris pack-out from the undercarriage and track frame, checking closely around the LN's narrower gauge where clearance is tighter. Grease boom, stick, bucket, and swing-bearing pin points. Check track sag and inspect shoes, rollers, and idlers for visible wear.
Every 250 h	Take a Cat S·O·S oil sample of the engine crankcase. Check swing drive and final drive oil levels. Inspect the engine air filter primary element and service it if the restriction indicator flags it. Check alternator and fan belt tension and condition. Clear debris from around the Clean Emissions Module to keep cooling airflow unblocked.
Every 500 h	Change engine oil and replace the engine oil filter. Replace the primary and secondary fuel filters. Take S·O·S samples of hydraulic oil, final drive oil, and swing drive oil. Check swing bearing mounting bolt torque. Check and adjust track sag on both sides.
Every 1,000 h	Replace the hydraulic system return and case-drain filter elements. Change oil in both final drives. Change swing drive oil. Inspect the turbocharger, engine mounts, and air intake piping for leaks or cracks. Check swing gear and pinion backlash and tooth wear.
Every 2,000 h	Replace the hydraulic tank breather and pilot filter elements. Sample engine coolant and check ELC concentration for freeze/boil protection; replace if degraded. Inspect boom, stick, and bucket cylinder rod seals for leakage or scoring. Run a full undercarriage wear inspection on track links, rollers, idlers, and sprockets. Re-torque track shoe bolts and recheck swing bearing bolt torque.
Every 4,500 h	Change hydraulic oil system-wide once S·O·S trending shows the HYDO Advanced additive package is depleted. Service Clean Emissions Module ash accumulation; clean or exchange the filter core per the regeneration/service indicator. Inspect and adjust engine valve lash on the C7.1 ACERT. Check injector performance and fuel system condition.
Every 6,000 h	Fully change engine coolant (Cat ELC) if it was not extended with ELC Extender treatment. Assess the swing bearing and gearbox for rebuild or replacement based on accumulated wear-inspection data. Inspect the main hydraulic pump and control valve for internal wear against cycle-time and drift symptoms logged over prior intervals. Evaluate undercarriage components for full rebuild versus continued top-up replacement, factoring in the LN's faster wear pace versus the L.

Servicing the 329E LN beyond the schedule

Predictive Maintenance & Fluid Analysis

Run S·O·S sampling on 329E LN engine oil, HYDO Advanced hydraulic oil, and TDTO final/swing drive oil at each interval to catch fuel dilution, soot loading, or gear wear metal before failure. Track the C7.1 ACERT's regeneration frequency and any derate warnings from the Clean Emissions Module; rising regen counts point to injector, turbo, or air-intake wear starting early. Log coolant sample results against ELC additive levels to protect the cooling system before a top-end overheating failure develops.

Corrective & Common Repairs

Grinding or knocking during swing points to a worn gearbox bearing or gear tooth. Catch it before the ring gear goes. Most hydraulic leaks trace to boom, stick, and bucket cylinder seals, hoses, and O-rings. The LN's narrower undercarriage packs mud and debris in tighter than the wider L gauge, pushing the travel motor face seal out of its bore faster. Keep the track frame clear. Check the C7.1's electronic fuel system and injectors on any starting or power complaint.

Overhaul & Rebuild Points

Undercarriage wear runs faster on the 329E LN than the L: its narrower gauge raises ground pressure and loads rollers, idlers, sprockets, and track links harder per hour. Budget rebuild earlier than an equivalent-hours L machine. Swing bearing and gearbox wear, tracked through backlash and bolt-torque checks, typically calls for rebuild at mid-life hours. Hydraulic pump and control valve wear shows up as slower cycle times or drift before it forces a full swap. Plan C7.1 top-end/injector overhaul and Clean Emissions Module service at the same milestones.

Seasonal & Environment Servicing

Switch to colder-rated engine oil and HYDO Advanced hydraulic oil grades before cold snaps to avoid cold-start wear. Check ELC coolant concentration for freeze protection each fall. Keep biodiesel blends at or below B20 in cold climates; higher blends gel faster in the fuel lines. On wet or muddy sites, clear packed debris from the LN's tighter undercarriage more often than an L-gauge machine to prevent face-seal damage. Cold ambient temperatures trigger more frequent parked regenerations on the Clean Emissions Module, so plan idle time for them.

329E LN fault codes & troubleshooting

Code	Meaning	Likely cause	What to do
247-14	Data link communication fault between the engine ECM and other machine control modules over the CAN/J1939 network	Intermittent J1939 data link wiring or connector fault, or an engine ECM software level that needs updating	Inspect data link wiring and connectors for damage or corrosion, confirm engine ECM software is at the current level, reprogram if a software fix is available, then clear and retest
1603-14	Machine control module fault flagged for special diagnostic instructions rather than a simple sensor failure	Internal machine control module fault or a communication issue with the module, often appearing alongside a data link code	Connect Cat ET, pull the specific special-instruction procedure tied to this code, check module wiring and connectors before replacing the module
100-01	Engine oil pressure reading below the normal operating range for current engine speed	Low oil level, worn or clogged oil pump/filter, or a faulty oil pressure sensor or its wiring	Stop and check oil level and condition first, inspect the pressure sensor and wiring, verify actual pressure with a mechanical gauge before returning to service
110-00	Engine coolant temperature reading above the normal operating range	Low coolant level, a plugged radiator or debris in the cooling fins, a stuck thermostat, a weak water pump, or a faulty coolant temperature sensor	Check coolant level and radiator condition once safely cooled, verify fan and thermostat operation, inspect sensor wiring, avoid shutting a hot engine down abruptly
168-04	Machine electrical system voltage reading below the normal range	Weak or failing battery, corroded or loose battery terminals and grounds, or a charging system/alternator fault	Load-test the batteries, clean and tighten terminals and ground straps, check alternator output and drive belt condition
190-08	Engine speed/timing sensor signal is abnormal in frequency or pulse pattern	Damaged or loose sensor wiring, incorrect sensor air gap, or damage to the timing wheel the sensor reads	Inspect sensor connector and harness for damage, check and reset sensor air gap per spec, replace the sensor if the signal stays erratic
41-04	8-volt sensor supply voltage from the engine ECM is below normal, which can cause several sensors to fault at once	A short to ground or chafed wiring on the shared sensor supply circuit, or a corroded connector	Check the 8-volt supply circuit and connectors for shorts or damage, isolate and test each sensor fed by the circuit, repair wiring before replacing sensors

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

329E LN attachments & work tools

Buckets

General-purpose buckets for this class run 1050-1200 mm (42-48 in) wide, roughly 1.3-1.6 m3 heaped capacity. Heavy-duty/rock buckets trend narrower, around 750-900 mm, in the 0.7-1.3 m3 range for higher abrasion and impact-rock digging. All mount on 90 mm (3.5 in) pins, either pin-on or through the machine's pin-grabber coupler family; exact capacity depends on width and duty rating ordered.

Hydraulic hammers

Breaker class for this excavator size matches the mid-size performance hammer range built for 25-32 t carriers, with tool/moil diameter around 150 mm and breaker service weight roughly 2,300-2,400 kg. Brand and exact blows-per-minute figures vary by manufacturer and configuration; always match hammer weight to the machine's approved lift/hydraulic capacity.

Quick couplers

This weight class uses a pin-grabber coupler rated for roughly 24-35 US ton carriers, with attachment pin diameter matching the bucket pin bore at 90 mm (3.5 in). The coupler lets one operator swap buckets, hammers, thumbs, and grapples without leaving the cab; the same coupler family is shared with the adjacent 324-class machine.

Thumbs/grapples

Hydraulic thumbs for this bucket size are typically non-progressive, single-cylinder, four-tooth units weighing roughly 700-750 kg and sized to pair with the 1050 mm (42 in) class bucket. Demolition and sorting grapples for this size range span a broad Cat product line covering roughly 10-45 t operating-weight carriers, with reinforced high-wear jaw edges for tear-down and material-sorting work.

Rippers

Single-shank rippers for this class use 90 mm pins matching the bucket/coupler family, with ear-to-ear spacing around 420 mm and pin center spacing around 485 mm, weighing approximately 650 kg. Used for breaking up rock, frozen ground, and paved surfaces ahead of the bucket.

Hydraulic-kit notes

The machine runs a high-pressure main hydraulic system with a back-to-back control valve as standard. Tool-driven attachments such as hammers, thumbs, and grapples need a dedicated auxiliary/tool hydraulic circuit, factory or dealer-fitted; exact flow and pressure settings vary by tool and should follow that tool's own spec sheet rather than one blanket figure.

All 329E LN assemblies by section

Every catalogued assembly group for the Caterpillar 329E LN. Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.

Machine Arrangement

338-3978 Common Ar

33***78

Common Ar

See all parts with full part numbers in Heavy Parts AI →

329E LN serial number reference

The PIN plate on a 329E LN sits on the right-hand side of the main frame near the base of the cab/upper structure, and the same number is restamped into the frame steel at the same spot so it survives if the plate is lost. Read the first 3 characters as the prefix (identifies the model/build series) and the following digits as the sequential unit number within that prefix.

Prefix	Identifies	Notes
RLD	329E L and 329E LN, long-narrow undercarriage version, Tier 4 Interim/Stage IIIB build	RLD00001-UP covers both the 329E L and 329E LN under one service manual set. LN is the long-narrow undercarriage option built on the same base machine as the L. Powered by the Cat C7.1 ACERT engine. Confirm the exact undercarriage code (L vs LN) against the machine's own configuration/attachment code on the PIN plate, not the prefix alone, since the prefix is shared between both configs.

Frequently asked questions

What engine powers the Caterpillar 329E LN?

The 329E LN uses the Cat C7.1 ACERT, a 7.01 L six-cylinder turbocharged diesel rated at 161 kW (216 hp) net flywheel power, with gross power quoted around 179-181 kW (241-243 hp) depending on which rating standard the factory sheet uses. It meets U.S. EPA Tier 4 Interim and EU Stage IIIB emissions through the Cat Clean Emissions Module, not a DEF/SCR system. This is a different engine from the 329D/329D L/329D LN, which used the smaller C6.6 ACERT.

What is the operating weight of the Caterpillar 329E LN?

Operating weight runs about 28,717-31,639 kg (63,310-69,750 lb) depending on boom, stick, counterweight, and track shoe width. The LN's narrower undercarriage sits near the middle of that range, commonly quoted around 29.5 t, and carries somewhat higher ground pressure than the same configuration on the wider-gauge 329E L.

What replaced the Caterpillar 329E LN?

Caterpillar replaced the E-series with the Tier 4 Final 329F line, which continued offering long and long-narrow undercarriage options on the same C7.1 ACERT platform. The 329E LN itself succeeded the C6.6 ACERT-powered 329D LN from the prior D-series generation.

What 329E LN owners discuss

How does the Cat C7.1 ACERT engine in the 329E LN compare to the engine in the prior D-series machines, and are there known weak points?

The 329E line moved to the C7.1 ACERT, a common-rail Tier 4/Stage IIIB engine that replaced the older HEUI-fuel-system engine used in the D-series. Owners and techs report it makes more power on less fuel than the previous series engine, with a fuel-burn improvement of roughly 3 percent doing comparable work. The known weak point: a failed turbocharger can push oil and debris back through the intake and emissions plumbing. If that debris isn't cleaned out thoroughly during the turbo repair, the engine can come up with low oil pressure and low compression afterward, sometimes requiring a bore-and-sleeve rebuild or full engine replacement. Have your dealer verify oil pressure and compression on any 329E LN with turbocharger history before it goes back to work.

What causes the intermittent power derate ("warm up mode") some 329E-family owners report that won't clear?

Reported cases trace to a fault code for an 8-volt DC sensor supply circuit reading above normal, not an engine mechanical fault. Symptoms are intermittent. The machine can sit in reduced-power warm up mode for an hour, clear on its own, then return for days at a stretch. Because the fault sits on a shared sensor supply circuit rather than one sensor, a systematic voltage-drop check across the harness and connectors finds it faster than swapping sensors one at a time. Have your dealer verify the sensor supply circuit before replacing parts.

What's behind the network data-link fault (an ECM-to-monitor communication code) some 329E displays show?

This fault flags a communication error between the machine ECM and the cab monitor over the machine's data link, not a physical wiring break. Caterpillar issued updated engine ECM software for Tier 4 excavators addressing this exact network fault strategy, and owners who caught the code found a dealer software update cleared it with no parts replaced. Worth checking flash file currency before chasing wiring on this one.

Mechanics sometimes can't find documentation for the OCV filter on a 329E. What is it?

It's a small filter element in the pilot and proportional valve (OCV) circuit that feeds the machine's electro-hydraulic control valves. It's easy to miss because general shop literature doesn't call it out clearly, and techs have had to pull it up through the dealer's electronic service lookup rather than a printed manual. If it gets skipped during routine filter service, contamination in that circuit shows up first as sluggish or erratic proportional-valve response.

What undercarriage wear pattern should owners of the narrow-gauge (LN) 329E watch for?

LN denotes the long, narrow-gauge undercarriage option, built for a tighter working width than the standard L undercarriage, useful on jobs that need to run in confined lanes or between obstacles. Wear behavior otherwise follows what's typical for a machine this weight class: watch the track adjuster and recoil spring for grease seepage or loss of tension, which shows up as a track needing re-tensioning more often than normal, then check idlers and rollers for play once the adjuster starts needing frequent attention. On the narrower gauge, that wear can show up sooner on one side on a machine that works a lot of sidehill or off-camber ground, since the narrower stance carries less side-load margin than the L undercarriage.

Are there hydraulic or swing behaviors specific to the 329E L/LN worth knowing before operating one?

The swing priority circuit on the 329E L/LN pairing uses an electrically controlled valve run through the machine ECM instead of a purely hydraulic valve. That gives finer, more programmable control when swinging into a truck under load, and operators moving from older Cat excavators notice the swing feels more metered rather than on or off. The machine also offers a heavy lift mode that raises system pressure for extra lift capacity in specific situations. Operators use it selectively since it isn't intended for continuous digging.

What should a buyer check before purchasing a used 329E LN?

Pull the ECM history for stored and active codes, especially the network data-link fault and the sensor supply-circuit derate code, and confirm the engine ECM software is current. Ask about turbocharger history, and if one was ever replaced, get oil pressure and compression checked rather than trusting a clean fault-code readout alone. Inspect the undercarriage adjuster and rollers for grease leaks or excess play, more critical on the narrow LN gauge since side-load wear can run uneven. Check the boom and stick welds and structural mounts for cracking given the machine's working hours, and review DPF and regen history since heavy idle time without full regens accelerates filter service needs. Always get an independent inspection and a dealer diagnostic pull before final purchase.

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

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