Caterpillar D30D
Maintenance schedule, common problems & OEM parts breakdown
The Caterpillar D30D is a medium-sized articulated dump truck designed for high-productivity earthmoving in rugged terrains. Produced starting in 1989, this machine features a Caterpillar 3306 engine delivering 285 hp (213 kW). The configuration includes a 5-speed transmission and a payload capacity of approximately 59,979 lb (27,206 kg), with heaped dump capacities reaching 22.5 yd³ (17.2 m³). It is part of a lineage of articulated haulers that include models like the D25D and D350D.
Across its production life, the D30D has remained a staple in the secondary market due to the reliability of the 3306 engine series. Maintenance focus has shifted toward advanced fluid analysis to prevent costly component failures. Today, the machine is highly valued in the used parts and equipment market for its robust chassis and standardized Caterpillar components, making it an economical choice for operators requiring durable, mid-range hauling capabilities.
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 D30D specifications
Engine
| Model | 3306 |
| Gross Power | 285 hp (212.6 kW) |
| Displacement | 640.8 cu in (10.5 L) |
Weights
| Total Empty Weight | 48,281.3 lb (21,900 kg) |
| Total Loaded Weight | 49,106 kg (108,260.3 lb) |
| Front Axle - Empty | 31,865.7 lb (14,454 kg) |
| Rear Axle - Empty | 16,415.7 lb (7,446 kg) |
| Front Axle - Loaded | 47,635.3 lb (21,607 kg) — varies by configuration |
| Rear Axle - Loaded | 27,499 kg (60,625 lb) |
| Rated Payload | 59,978.97 lb (27,206 kg) |
Dimensions
| Overall Length | 29.14 ft in (8,880 mm) |
| Overall Width | 10.83 ft in (3,300 mm) |
| Overall Height | 11.16 ft in (3,400 mm) |
| Wheelbase | 16.25 ft in (4,950 mm) |
| Dump Height | 17.92 ft in (5,460 mm) |
Performance
| Max Speed | 32.4 mph (52 km/h) |
| Number of Forward Gears | 5 |
| Heaped Capacity | 17.2 m³ (22.5 yd³) |
| Struck Capacity | 16.49 yd³ (12.6 m³) |
Service capacities (summary)
| Fuel Capacity | 118.9 gal (450 L) |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
D30D fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Fuel tank | 450 L (118.9 US gal) | Not documented |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Caterpillar D30D maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 10 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
Servicing the D30D beyond the schedule
Predictive Maintenance & Fluid Analysis
Utilize Cat S.O.S Services to monitor engine oil, hydraulic fluid, and coolant. Analyze samples for wear metals like iron or copper, and contaminants such as silicon (dirt) or sodium (coolant). For the D30D, checking for fuel dilution in engine oil is critical to prevent injector damage. Regular analysis at 250-hour intervals provides early warning of pump or bearing degradation before catastrophic failure occurs.
Corrective & Common Repairs
Common repair focus areas include the articulation joint, steering pins, and hydraulic hoses prone to abrasion. Inspect for leaks at the hydraulic cylinders and check for air leaks in the turbocharger system. If the engine exhibits abnormal smoke or noise, evaluate the fuel system and air intake. Ensure all hydraulic fittings are tight to prevent cavitation caused by air ingestion into the pump.
Overhaul & Rebuild Points
Major overhaul milestones include a full transmission service and hydraulic oil replacement at 2,000 hours. Evaluate the engine for top-end rebuild if compression or oil consumption increases. During structural inspections, check the integrity of chassis welds and articulation point bushings. Replacing worn pins and bushings is essential to maintain steering precision and prevent excessive play in the articulated frame.
Seasonal & Environment Servicing
In high-dust or quarry environments, shorten air filter inspection intervals to daily and replace elements more frequently. In hot climates, optimize hydraulic oil drain intervals and clean radiator fins daily to prevent overheating. For cold weather operations, use appropriate SAE 10W/30 engine oil for better starting capability and ensure all grease points are serviced with high-quality lubricants to prevent component binding.
D30D common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 8M-3182 | Spring,Helical,Comp Engine Oil Filter Assembly | Lubrication service | Check fitment → |
| 2P-2537 | Stud Engine Oil Filter | Lubrication service | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
D30D fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| 110-0 | Engine Coolant Temperature — Above Normal | Low coolant level or thermostat failure | Inspect cooling system and refill coolant |
| 110-3 | Engine Coolant Temp Sensor — Voltage High | Open circuit or sensor failure | Check wiring and replace sensor if faulty |
| 174-3 | Engine Fuel Temperature — Voltage Above Normal | Open circuit in sensor wiring | Inspect harness and replace sensor if necessary |
| 190-8 | Engine Speed — Abnormal Frequency | Speed sensor air gap, sensor failure, or tone ring damage | Check sensor gap and test speed sensor/tone ring |
| 41-3 | 8-Volt DC Supply — Voltage Above Normal | Short to power on 8V reference circuit | Inspect sensors sharing the 8V supply and isolate fault |
| 41-4 | 8-Volt DC Supply — Voltage Below Normal | Short to ground on 8V reference circuit | Disconnect sensors one at a time to locate short |
| 2348-9 | SAE J1939 Data Link #2 — Abnormal Update Rate | CAN bus wiring damage or termination fault | Check CAN wiring and measure termination resistance |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
D30D attachments & work tools
Dump Body Configurations
The machine features a dump body with a struck capacity of 16.49 yd3 (12.6 m3) and a heaped capacity of 22.5 yd3 (17.2 m3). Material handling options include steel bodies for abrasive loads or aluminum bodies for improved durability.
Mounting and Configuration
Standard operating dimensions vary by configuration, with a typical length of 30 ft 0 in (0 mm) and width of 9 ft 6 in (152.4 mm). The dump height is rated at 17.92 ft (5462.784 mm).
Hydraulic and Engine Systems
The unit is powered by a Caterpillar 3306 engine providing 212.6 kW (285 hp). Hydraulic system maintenance requires high-quality fluids such as Cat HYDO Advanced to prevent component damage.
All D30D assemblies by section
Every catalogued assembly group for the Caterpillar D30D. Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Basic Engine
284-7811 Kit-Hardware
| 0L***43 | Bolt 63.5 mm (3/8" X 2 1/2" -Cover Assembly To Fender | 1 |
| 0S***91 | Screw,Cap,Hexagon Bearing Retainer; Part Of Kit P/N 1w***82 | 2 |
| 0S***94 | Bolt (1 In. Long 3/8 In. Dia.); Plate Assembly To Support Assembly | 2 |
Engine Arrangement
284-3287 Conversion Ar-Engine
| 0R***14 | Rod As-Connecting | 1 |
| 0R***97 | Cylinder Pack Group | 6 |
| 0R***82 | Injector As | 6 |
Fuel System
7c-8993 Fastener Gp-Fuel Inj Pump
| 0S***14 | Bolt (.25" Diameter-.50" Long) | 3 |
| 2S***83 | Bolt (3.25" Long-Drilled Head) | 1 |
| 4F***57 | Screw,Cap,Hexagon H Shock Mount To Bracket | 8 |
111-5162 Control Gp-Fuel Ratio
| 10***93 | Washer | 1 |
| 11***62 | Control Group-Fuel Ratio (Basic) | 1 |
| 11***58 | Washer; (12.7x6.65x0.79-mm Thk) | 1 |
2w-2410 Governor Gp
| 03***16 | Bolt-Self Locking; (1/4unc X 3/4) | 3 |
| 0S***16 | Screw,Cap,Hexagon H Receptacle Mtg; Bolt Brackets To Firewall Assembly | 6 |
| 13***07 | Seal-Lip Type; (6.39mm) | 1 |
4p-9827 Pump Gp-Fuel Injection
| 1W***87 | Valve As-Check; (Fuel Injection Pump) | 1 |
| 4P***27 | Pump Group-Fuel Injection | 1 |
| 4P***30 | Plunger & Barrel Assem. | 1 |
115-9595 Pump Gp-Fuel Injection
| 0S***15 | Bolt 19 mm (.75 In.) Long Return Air Console To Enclosed Rops | 4 |
| 11***18 | Seal-O-Ring; (26.64mm Id) | 6 |
| 11***95 | Pump Group-Fuel Injection | 1 |
7c-8992 Seal Gp-Pump
| 03***79 | Seal-O-Ring (Id=10.82mm) | 1 |
| 14***77 | Gasket | 1 |
| 15***26 | Gasket | 1 |
1w-1597 Torque Control Gp
| 1P***52 | Insulator,Bushing Governor | 1 |
| 1W***97 | Torque Control Group | 1 |
| 2P***85 | Spacer (.635 mm Thk); (0.635-mm Thk) | 1 |
Service Equipment And Supplies
284-3299 Kit-Engine Parts
| 10***68 | Hose As | 1 |
| 10***69 | Tube As; (Oil) | 1 |
| 12***74 | Clip-Loop; (12.7mm Id) | 1 |
D30D serial number reference
The machine ID plate is typically located on the outer frame of the equipment. The serial number consists of a three-character alphanumeric prefix followed by a five-digit sequence ID.
| Prefix | Identifies | Notes |
|---|---|---|
| 3AJ | D30D Articulated Truck | Covers serial number range 3AJ00001 to 3AJ00414. Engine output is rated up to 213 kW (285 hp). Machine weight is approximately 21.9 t. Dump capacity is 17.2 m³ (22.5 yd³). Standard operating dimensions include a length of 30 ft 0 in (0 m), width of 9 ft 6 in (0.15 m), and height of 10 ft 9 in (0.23 m). Production period began in 1989. |
Frequently asked questions
What engine powers the Caterpillar D30D?
The Caterpillar D30D is powered by a Caterpillar 3306 engine, providing 285 hp (213 kW) of gross power.
What is the operating weight of this machine?
The total empty weight is approximately 48,281.3 lb (21,900 kg), while the total loaded weight reaches approximately 108,260.3 lb (49,100 kg).
What machine replaced the D30D?
Specific successor model names are not documented in the provided technical data; however, it belongs to a class of medium-sized articulated haulers alongside models like the 725 C and 745 C.
What D30D owners discuss
What are the known engine performance issues associated with the D30D series?
What specific structural wear patterns should be inspected on the D30D chassis?
What are common electrical failure symptoms in Caterpillar machines of this era?
What hydraulic behaviors indicate a need for system maintenance?
What should be checked when purchasing a used Caterpillar D30D?
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
Need a specific D30D part?
Search live OEM part data, check fitment, and cross-reference alternatives with Heavy Parts AI.