Caterpillar 980C
Maintenance schedule, common problems & OEM parts breakdown
The Caterpillar 980C is a mid-size wheel-type loader built from roughly the late 1970s into the mid-1980s, sitting in Cat's medium wheel loader class. It runs the Cat 3406 turbocharged diesel, an inline six-cylinder, 14.6 L engine rated at 270 hp (201.3 kW) net, mechanically governed with no electronic engine control. Operating weight runs roughly 26.3-27.6 t (58,000-60,900 lb), varying by bucket, tire, and counterweight configuration. Cat offered the 980C with general-purpose bucket and aggregate-handler arrangements; work tools mount pin-on/bolt-on since this generation predates Cat's hydraulic quick-coupler. It falls in the lineage between the 980B it replaced and the 980F / 980F II that succeeded it, ahead of the later 980G, 980G II, and 980H.
Across the run, Caterpillar carried the 980C's core mechanical layout forward with running production and configuration updates rather than a clean-sheet redesign; the 980C itself is a fully mechanical machine, with a mechanical governor and no ECM or onboard electronic diagnostics, which keeps troubleshooting straightforward compared to later electronically controlled loaders. That simplicity is a big part of why it still holds value in the used and parts market today: wide OEM and aftermarket parts support, a drivetrain any diesel shop can diagnose without specialized electronic tooling, and a reputation for being economical to keep running. Buyers evaluating a used 980C should budget for implement and steering hydraulic pump wear and articulation/linkage bushing wear, the two areas that show up most often on high-hour machines.
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 980C specifications
Engine
| Engine model | Cat 3406 turbocharged diesel (era literature also references 3406T for early production and 3406C for later production within the 980C run), inline 6-cylinder, 4-stroke |
| Net power | 270 hp (201.3 kW) |
| Displacement | 14.6 L (891-893 cu in) |
| Cylinders | 6, inline |
| Emissions tier | Predates EPA/EU nonroad emissions tier regulation (production ran through the late 1970s into the mid-1980s, before Tier standards took effect) |
Weights
| Operating weight | approx. 26,300-27,600 kg (58,000-60,900 lb); varies by configuration/source |
| Static tipping load (full turn) | 18,490 kg (40,763.5 lb) |
Dimensions
| Overall length (bucket on ground) | 8.62-8.63 m (28 ft 3 in) |
| Overall width (across standard bucket) | 3.37-3.38 m (11 ft 0 in-11 ft 1 in) |
| Overall height (to cab top) | 3.78-3.84 m (12 ft 5 in-12 ft 7 in); some listings give overall transport height up to 4.09 m (13 ft 5 in) including exhaust stack, varies by source |
| Dump clearance at max raise | 3.17-3.20 m (10 ft 5 in-10 ft 6 in) |
| Wheelbase / ground clearance | Not consistently published for this model across available sources |
Performance
| Travel speed, forward (top gear) | 24.6-24.7 km/h (15.3 mph) |
| Travel speed, reverse (top gear) | 39.6-39.75 km/h (24.6-24.7 mph) |
| Transmission speeds | 4 forward / 4 reverse, powershift automatic |
| Breakout force | 261.9 kN (58,880 lb) |
| Bucket capacity, heaped (general-purpose bucket) | 4.0-4.05 m3 (5.24-5.3 yd3) |
| Hydraulic cycle times | Raise approx. 7.3 sec, dump approx. 2 sec, lower (float down) approx. 3.4 sec |
Service capacities (summary)
| Fuel tank | 400 L (105.7 US gal) |
| Hydraulic system | 208 L (55 US gal) |
| Engine oil | Not consistently published for this model across available sources - verify exact refill capacity with your dealer or the OEM service manual |
| Cooling system | Not consistently published for this model across available sources - verify exact refill capacity with your dealer or the OEM service manual |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
980C fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) - Cat 3406T turbocharged diesel | 28 L (7.4 US gal) | Cat DEO (Diesel Engine Oil), multigrade. SAE 10W-30 for ambient roughly -18 deg C to 40 deg C (0 deg F to 104 deg F); SAE 15W-40 for warmer ranges, per the OMM ambient-temperature chart. Confirm against your OMM before ordering bulk oil. |
| Cooling system | Not consistently documented for this specific model/serial range in available references. Comparable 3406-powered Cat wheel-loader chassis of the same era typically run 40-60 L (10.5-16 US gal); confirm the exact figure on your OMM lubrication chart or with your dealer. | Cat DEAC (Diesel Engine Antifreeze/Coolant), 50/50 premix, period-correct for this build; Cat ELC (Extended Life Coolant) is the modern Cat-recommended equivalent if converting the system. |
| Fuel tank | 400 L (105.7 US gal) | Diesel fuel per Cat fuel specification (No. 2-D grade typical for this era). |
| Transmission (powershift) | 62 L (16.4 US gal) | Cat TDTO (Transmission/Drive Train Oil) meeting Cat TO-4 spec. Grade selected by ambient temperature per the OMM chart - typically SAE 10W in cold conditions up to SAE 30 or 50 in warm conditions. |
| Differential and final drive - front axle | 87 L (23.0 US gal) | Cat TDTO (TO-4 spec), SAE 10W/30/50 selected by ambient temperature. Fill to the level plug rather than to an exact quantity, since actual fill varies by configuration. |
| Differential and final drive - rear axle | 81 L (21.4 US gal) | Cat TDTO (TO-4 spec), SAE 10W/30/50 selected by ambient temperature. Fill to the level plug rather than to an exact quantity, since actual fill varies by configuration. |
| Hydraulic system (tank plus lines) | 208 L (55.0 US gal) total system. Hydraulic tank alone is approximately 125 L (33.0 US gal) (unconfirmed split - check your OMM). | Cat multigrade diesel-type hydraulic oil (Cat DEO-equivalent) or Cat TDTO, grade selected by ambient temperature per the OMM chart. Some later parts/service literature for this platform references Cat HYDO as the updated equivalent - confirm the exact callout for your serial prefix. |
| Grease (all chassis and pin points) | Not applicable - service-point application, no bulk refill capacity. | Cat Multipurpose Grease, NLGI 2, for general chassis and low-load pin points. Cat Advanced 3Moly Grease for high-load pivot pins and bucket linkage points where called out in the lubrication chart. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Caterpillar 980C 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 980C beyond the schedule
Predictive Maintenance & Fluid Analysis
Run oil sampling on the engine, transmission, differentials, and hydraulic tank at every scheduled drain to catch wear-metal trends before the mechanically governed 3406 or the powershift transmission fail outright. This generation has no ECM or onboard diagnostics, so fluid and coolant sampling are the earliest warning system available. Track hydraulic sample trends closely; implement and steering pump seals are the 980C's most common failure point, and rising silica or metal counts in hydraulic samples usually flag pump wear before a leak or slow cycle time appears.
Corrective & Common Repairs
Expect implement and steering hydraulic pump seal replacement to be the most frequent repair on a working 980C; slow lift/tilt response or steering lag traces back here before the main pump. Loader linkage and articulation pins wear faster on machines skipping the 50-hour grease interval, producing clunk on direction changes. Because there's no hydraulic quick coupler, expect wear at the pin-on bucket/tool mounting points. Torque converter and transmission clutch pack issues show up as delayed engagement or slipping shifts; pull a transmission oil sample before tearing into the powershift.
Overhaul & Rebuild Points
A 980C rebuild centers on the mechanically governed 3406 engine: injectors, valve train, and turbocharger are the top-end items to plan for, since this engine predates electronic diagnostics and wear is best tracked through compression checks and oil analysis. On the chassis, budget for articulation center-pin and loader linkage bushing replacement, plus differential and final-drive inspection at all wheel stations. Hydraulic pump rebuilds are common enough on high-hour machines to treat as planned overhaul work rather than an emergency repair.
Seasonal & Environment Servicing
Cold-weather starts on the mechanical 3406 benefit from a block heater and correct-viscosity engine oil; with no ECM to manage cold-start fueling, glow-plug/ether aids and battery condition matter more. Shorten the articulation and linkage grease interval below 50 hours in muddy, sandy, or high-dust sites, since those conditions accelerate pin and bushing wear on this pin-on-only machine. In hot or dusty climates, check the radiator and oil cooler cores more often for packed debris, and tighten the fuel-tank water-separator and cab air filter checks during wet seasons.
980C common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 8T-6765 | Plug-Pipe | Scheduled service item | Check fitment → |
| 9S-8752 | Nut-Full | Scheduled service item | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
980C fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| Torque Converter Oil Temperature - HIGH (red gauge segment / warning light) | Transmission (torque converter) oil temperature sender signals oil above the normal operating range. | Failed or drifting temperature sender/wiring giving a false-high reading; low oil level; plugged oil cooler; torque converter slip from overload or wrong oil grade. | Verify actual oil temperature with a handheld thermometer before condemning the sender; check oil level and cooler for restriction; replace the sender if the gauge disagrees with measured temperature. |
| Engine Coolant Temperature - HIGH (red gauge segment / warning light) | Engine coolant temperature sender signals coolant above the normal operating range. | Low coolant level, plugged radiator core or debris screen, slipping or failed fan drive, faulty sender. | Shut down safely and allow cooling; check coolant level and radiator for blockage; verify fan operation; confirm the reading with a manual thermometer before replacing the sender. |
| Engine Oil Pressure - LOW (red warning light) | Engine oil pressure sender/switch signals pressure below the safe minimum for the mechanically governed diesel. | Low oil level, worn oil pump or bearings, plugged oil filter or suction screen, faulty sender or switch. | Shut the engine down immediately, check oil level and filter condition, and verify with a mechanical test gauge before further operation. |
| Alternator / Charging System warning light | Charging system voltage has dropped below normal; alternator not charging the battery circuit. | Worn or broken drive belt, faulty alternator, loose or corroded battery/charging wiring. | Check belt tension and condition, test battery voltage with the engine running, and inspect wiring and alternator output. |
| Transmission Oil Filter Bypass indicator | Mechanical bypass indicator shows the transmission oil filter has enough restriction that oil is bypassing the element unfiltered. | Filter element loaded with debris; cold oil not yet warmed up (temporary pop); degraded oil. | Run the engine to normal operating temperature and recheck; replace the filter element if the indicator stays popped. |
| Air Filter Restriction indicator (mechanical service gauge) | Vacuum-actuated indicator on the air intake shows the dry-type air filter element is restricting intake airflow. | Dirty or clogged primary air filter element, damaged element, restricted intake piping. | Inspect and clean or replace the primary filter element per service interval, reset the indicator, and recheck at operating rpm. |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
980C attachments & work tools
General purpose buckets
Standard heaped general-purpose bucket for the 980C runs about 4.0-4.05 m3 (5.24-5.3 cu yd) at roughly 3.37-3.38 m (11.06-11.1 ft) width, sized to the machine's 3406-engine power class. Figures are consistent across spec sheets within normal rounding; treat small width/capacity spread as configuration variance, not separate models.
Rock and heavy-duty buckets
Reduced-capacity, reinforced buckets with added wear protection are a standard work-tool family for loaders in this size and weight class, used in quarry and aggregate loading where abrasion outweighs volume. Exact 980C-specific capacity figures are not documented in available literature — confirm current options with a dealer.
Multi-purpose (4-in-1) buckets
4-in-1 buckets that clamp, dose, grade, level and dump are offered across this loader size class and run off the machine's tilt hydraulic circuit with an added clam cylinder and extra hydraulic line. Capacity on a 4-in-1 bucket runs smaller than an equivalent GP bucket on the same carrier.
Pallet and material forks
Bolt-on or pin-mounted fork frames with tine sets are a common material-handling work tool for loaders this size, used for palletized loads, pipe, and yard material. Rated tine capacity is not documented for the 980C specifically — confirm load rating for a given fork frame with a dealer.
Log and lumber forks
Large wheel loaders in this weight class are commonly fitted with log or lumber forks for mill-yard and forestry material handling. No 980C-specific rated capacity was found in available literature; treat as a size-class-typical option pending dealer confirmation.
Work-tool mounting / coupler system
Work tools on this generation of large wheel loader mount pin-on/bolt-on to the lift arms and tilt linkage; no hydraulic quick-coupler system is documented specifically for the 980C. Cab-operated hydraulic quick-couplers appear on later, separate Cat wheel loader lines and should not be assumed to carry over to this generation.
Ground engaging tools
Buckets take bolt-on cutting edges or bolt-on teeth with adapters, chosen by material type and abrasion level. Edge or tooth selection is independent of bucket capacity and varies by application.
Waste and scrap guarding
Wheel loaders in this class are commonly ordered with added guarding — screens over the radiator and engine bay, window and light guards — for transfer-station, scrap-yard, and demolition duty. This is a recognized option family for the size class; a 980C-specific factory guarding package was not confirmed in available literature.
Tires
Base tire fitment documented for the 980C is 26.5-25, 20 PR, L-4 rock-service tread. Other tread ratings (L-3 general purpose, L-5 extra-deep tread) are typical alternates offered across this loader class; confirm availability for a given serial range with a dealer.
All 980C assemblies by section
Every catalogued assembly group for the Caterpillar 980C. Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Basic Engine
304-6674 Kit-Hardware
| 03***19 | Bolt; --To Bearing Ret. At Lower Front Shaft Bore | 11 |
| 0L***70 | Bolt (2-1/4") Filler Tube Assembly To Transfer Drive Case | 1 |
| 0S***71 | Screw,Cap,Hexagon; Tube Assembly To Turbocharger And Elbow Mounting | 3 |
Engine Arrangement
304-6669 Conversion Ar-Engine
| 03***79 | Seal-O-Ring (Id=10.82mm) | 1 |
| 0R***80 | Rod As-Connecting | 1 |
| 0R***47 | Cylinder Pack Group | 6 |
304-6660 Conversion Ar-Engine
Fuel System
9y-1234 Fastener Gp-Fuel Inj Pump -Governor
| 1B***16 | Bolt; (1/4-20x5-In) | 2 |
| 4F***57 | Screw,Cap,Hexagon H Shock Mount To Bracket | 2 |
| 5B***40 | Bolt; (1/4-20x1-In) | 2 |
7c-4797 Governor Gp
| 03***16 | Bolt-Self Locking; (1/4unc X 3/4) | 3 |
| 0S***47 | Bolt; (1/4-20x0.75-In)(Drilled Head) | 2 |
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 1 |
104-4409 Pump Gp-Fuel Injection
| 0S***15 | Bolt 19 mm (.75 In.) Long Return Air Console To Enclosed Rops | 14 |
| 10***09 | Pump Group-Fuel Injection | 1 |
| 10***52 | Camshaft-Fuel Pump | 1 |
108-6633 Pump Gp-Fuel Injection
| 10***02 | Bonnet-Valve | 1 |
| 10***04 | Plunger & Barrel As | 1 |
| 10***33 | Pump Group-Fuel Injection | 1 |
2w-8628 Torque Control Gp
| 1P***52 | Insulator,Bushing Governor | 1 |
| 2P***85 | Spacer (.635 mm Thk); (0.635-mm Thk) | 1 |
| 2W***34 | Bar-Load Stop; (4.0mm Thk) | 1 |
Service Equipment And Supplies
304-6665 Kit-Engine Parts
| 03***46 | Elbow, 90 Deg Adj., 1/4in. J.I.C. X 7/16in.-14 Str. Thd. | 1 |
| 06***40 | Seal-O-Ring (Id=37.69mm) | 1 |
| 10***48 | Ring-Guide | 1 |
304-6662 Kit-Engine Parts
| 03***46 | Elbow, 90 Deg Adj., 1/4in. J.I.C. X 7/16in.-14 Str. Thd. | 1 |
| 06***40 | Seal-O-Ring (Id=37.69mm) | 1 |
| 10***48 | Ring-Guide | 1 |
307-2967 Kit-Engine Parts
| 03***46 | Elbow, 90 Deg Adj., 1/4in. J.I.C. X 7/16in.-14 Str. Thd. | 1 |
| 06***40 | Seal-O-Ring (Id=37.69mm) | 1 |
| 10***48 | Ring-Guide | 1 |
980C serial number reference
The PIN plate on a 980C is a riveted metal tag on the left side of the main frame, near the operator's station/articulation area (check the operator's manual diagram if it is hard to spot, and clean off grime for a clear read). Read the first three characters as the letter/number prefix that identifies the production block, then the digits after it as the sequential unit number within that block. The engine, transmission, and other major components carry their own separate serial plates and prefixes - do not confuse those with the machine's own PIN.
| Prefix | Identifies | Notes |
|---|---|---|
| 63X | Standard 980C production block | Main, highest-volume 980C production block. Runs from the low unit numbers into the 7000-plus range, late 1970s into the mid-1980s. Fitted with the Cat 3406 turbocharged, air-to-air aftercooled diesel (about 270 hp) and a powershift transmission. Engine, transmission, and axle/differential assemblies carry their own separate serial prefixes, distinct from the machine PIN. |
| 13B | 980C production block (early-mid 1980s) | 980C production block, early-to-mid 1980s. Powered by the 3406 engine. Parts catalog cooling system and hydraulic gear pump sections list it as its own machine block. A field-reported unit sits in the low thousands of the sequence range. Runs parallel to the 63X block, not a straight replacement for it. |
| 2XD | 980C production block (mid-1980s) | 980C production block, mid-1980s. Powered by the 3406 engine. Parts catalog component serial effectivity (radiator group) starts near the low hundreds of the sequence range. A real unit in the low thousands of the sequence range corroborates the block. |
| 2EB | 980C production block, confirm with dealer | 980C production block alongside 63X, 13B, and 2XD. Powered by the 3406 engine. Exact serial range and production years not independently confirmed beyond parts catalog listings. Verify with your dealer before relying on it. |
Frequently asked questions
What engine does the Caterpillar 980C use?
The 980C runs the Caterpillar 3406, a turbocharged inline six-cylinder diesel displacing 14.6 L, rated at 270 hp (201.3 kW) net. It's mechanically governed with no electronic engine control, typical of this production era.
What is the operating weight of the Caterpillar 980C?
Operating weight runs roughly 26.3-27.6 t (58,000-60,900 lb), varying with bucket type, tire choice, and counterweight configuration. Check the build sheet for the exact figure on a given serial number.
What replaced the Caterpillar 980C?
Caterpillar replaced the 980C with the 980F, later updated as the 980F II, before the line moved on to the 980G, 980G II, and 980H. The 980C itself succeeded the 980B.
What 980C owners discuss
What transmission or torque-converter symptoms are typical on a high-hour 980C?
Which hydraulic pump tends to fail first on a 980C, and what does that look like?
Are there known quirks with the 980C's 3406 engine?
What brake issues come up on the 980C, and how serious are they?
What wear patterns show up on the loader linkage and tires?
Are there electrical or sensor issues specific to the 980C?
What should a buyer check when looking at a used 980C?
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
Need a specific 980C part?
Search live OEM part data, check fitment, and cross-reference alternatives with Heavy Parts AI.