Caterpillar Engines for Sale: C7, C9, C15, C15 ACERT, 3306, 3406E & Full CAT Range

The Caterpillar Engine Range: Every Platform from C7 to C18

The Caterpillar diesel engine range spans a broader application scope than any other single heavy equipment engine manufacturer, from compact mid-range platforms powering medium excavators and motor graders through to high-displacement, high-output powerplants that drive the largest machines in open-cut mining and bulk earthmoving. Understanding where each CAT platform sits within that range is the foundation of sourcing the correct replacement engine for your application.

The full CAT diesel engine range we cover at Imara Engineering:

• CAT C7 — a 7.2-litre six-cylinder mid-range platform widely deployed in medium excavators, motor graders, wheeled loaders, and a broad range of mid-size CAT-powered equipment across construction and infrastructure applications globally
• CAT C9 — a 9.3-litre six-cylinder platform deployed across a wide range of CAT equipment types, including excavators, articulated trucks, road machinery, known for its reliable performance and consistent demand for replacement engine assemblies at high machine hours
• CAT C12 — a 12-litre high-torque six-cylinder platform deployed across large excavators, heavy haul trucks, and high-output CAT-powered plant equipment, with strong ongoing demand for rebuilt units
• CAT C13 — a 13-litre six-cylinder platform widely used across large excavators, haul trucks, motor graders, and heavy plant equipment globally, one of the most widely deployed modern CAT engines with strong replacement demand at high hours
• CAT C15 — the most widely replaced CAT engine in heavy industry. The standard C15 in its 15-litre six-cylinder configuration became the benchmark powerplant for large excavators, heavy haulage trucks, and high-production plant equipment across global fleets
• CAT C15 ACERT — the ACERT variant of the C15, incorporating Caterpillar's Advanced Combustion Emissions Reduction Technology. The highest-demand CAT engine assembly in our range, a well-documented platform for replacement demand driven by the specific wear and failure characteristics of the ACERT combustion system at high engine hours
• CAT C16 — a 16-litre high-output platform for the largest excavators and heavy haul applications demanding maximum torque output
• CAT C18 — Caterpillar's highest-displacement current-production six-cylinder platform, producing up to 765 horsepower in high-output configurations for the most demanding mining and heavy haul applications
• CAT 3306 — one of the most widely produced CAT diesel engines in history, powering generations of excavators, dozers, motor graders, and heavy plant across global fleets. Strong and consistent replacement demand from operators maintaining older machines, where the 3306 remains the most cost-effective power plant in service
• CAT 3406, 3406E & 3406B — the most rebuilt CAT engine family in existence. The 3406E in particular remains one of the most highly regarded large diesel engines ever produced — combining proven mechanical reliability with strong global parts availability and an unmatched global network of rebuild expertise
• CAT 3208 — a V8 diesel platform widely deployed in excavators, marine applications, and generator sets across multiple decades of production
• CAT 3116 & 3126 — reliable mid-range CAT platforms with broad application coverage across construction, marine, and industrial equipment types

Used Caterpillar Engines for Sale, Cost-Effective Replacement for Defined Applications

A used Caterpillar engine is a tested, running unit removed from a machine with documented service history. For operators working within a defined budget, a machine with a shorter remaining operational life expectation, or an application where the investment in a rebuilt unit is not justified by the projected machine utilisation, a used CAT engine is a viable and cost-effective replacement path, provided the unit has been properly assessed, and its history is documented.

At Imara Engineering, every used Caterpillar engine in our inventory is assessed before listing:

• Compression and oil pressure are tested before the unit is listed for sale
• Service history and removal documentation were reviewed and disclosed where available
• Known failure history or major prior repairs communicated before sale commitment
• Engine serial number and build specification confirmed for correct fitment matching to your machine

Used Caterpillar engines are most appropriate when:

• The machine has a defined and shorter remaining operational life, where a full rebuild investment is not justified
• The application is lower-cycle or lower-load than the machine from which the engine was removed
• A bridge solution is required to return a machine to productivity while a longer-term rebuild plan is developed
• Budget constraints make a reconditioned or rebuilt unit impractical for the specific application

Our team will advise honestly on whether a used CAT engine is the correct choice for your operational objectives or whether the additional investment in a reconditioned or rebuilt unit better protects your cost and reliability targets

Rebuilt Caterpillar Engines for Sale; Full OEM Specification Restoration

A rebuilt Caterpillar engine is the highest quality engine replacement path available outside of a new factory unit. Every component in the engine is measured, assessed, and either confirmed as within OEM specification or replaced with a new or remanufactured part, resulting in an engine that, at the point of reassembly, meets the same internal dimensional specifications as a new CAT engine leaving the factory.

Imara Engineering's rebuilt Caterpillar engines are assembled to OEM dimensional tolerances throughout:

• Crankshaft reground or replaced to OEM journal specifications with new main and rod bearing shells installed
• Cylinder bores measured, honed, or sleeved to OEM bore diameter and surface finish specification
• New pistons and piston rings installed to OEM piston-to-bore clearance specifications
• Camshaft is measured and replaced where lobe wear is confirmed, with followers replaced alongside the camshaft on all platforms
• Cylinder head reconditioned or replaced with valve seats, guides, springs, and seals replaced throughout
• A completely new gasket kit and sealing system were installed throughout the engine
• Full assembly to OEM torque specifications with a documented build sheet for every engine
• Post-build compression testing, oil pressure verification, and operational testing before dispatch

For operators committing a machine to full production service life mining operations, high-cycle civil construction, heavy haulage, a rebuilt Caterpillar engine from Imara Engineering is the most reliable and best-documented replacement path available outside the CAT factory.

Remanufactured Caterpillar Engines for Sale; Understanding CAT Reman

The term remanufactured Caterpillar engine or CAT reman refers specifically to engines remanufactured through Caterpillar's own factory remanufacturing program — a process carried out at CAT's own reman facilities using new and remanufactured CAT components, machined to factory tolerances, and dispatched with a CAT factory warranty. CAT reman engines are identified by specific CAT part numbers and carry warranty terms backed by the Caterpillar dealer network.

At Imara Engineering, our rebuilt and reconditioned Caterpillar engines are independently rebuilt engines assembled to OEM dimensional and performance specifications using OEM-equivalent components; they are not CAT factory reman units. The distinction matters for operators who specifically require a factory CAT reman unit for warranty compliance, fleet management protocols, or dealer network servicing requirements.

For the majority of heavy equipment replacement applications globally where OEM-equivalent performance, documented build quality, and competitive pricing are the primary requirements, our rebuilt Caterpillar engines deliver the same dimensional integrity and operational reliability as a factory reman at a more accessible price point. Contact our team directly if your application specifically requires a factory CAT reman unit, and we will advise on availability and lead time for your model and serial number.

CAT C15 Engines for Sale; The Highest-Demand Platform in Our Range

The CAT C15 is the most widely replaced diesel engine assembly in our entire range, and for good reason. The 15-litre six-cylinder C15 became the benchmark powerplant for large excavators, heavy haulage trucks, and high-production plant equipment across global fleets from the late 1990s onward, and the sheer volume of C15-powered machines still in active heavy-duty service globally means demand for used, rebuilt, and remanufactured C15 engines remains consistently high.

The C15 platform exists in two distinct variants that must be confirmed by engine serial number before any replacement engine or component is sourced:

CAT C15 (6NZ & MBN prefixes) The pre-ACERT C15 is the standard C15 configuration before the introduction of the ACERT combustion system. The 6NZ is the most widely recognised C15 serial prefix and one of the most highly regarded CAT diesel engines for rebuild longevity and mechanical reliability. Rebuilt 6NZ C15 engines remain in high demand across global heavy equipment fleets.

CAT C15 ACERT (C15 with ACERT prefix serials). The ACERT variant incorporates Caterpillar's Advanced Combustion Emissions Reduction Technology, a system that operates at higher combustion pressures and with more complex valve timing and emissions management than the standard C15. The C15 ACERT carries well-documented replacement demand driven by the specific failure characteristics of the ACERT combustion system at high engine hours, including camshaft lobe spalling, head gasket failure under sustained load, and piston ring wear at elevated hours.

Both variants are available from Imara Engineering as used, rebuilt, and remanufactured units, all confirmed by engine serial number prefix before dispatch.

CAT 3406E Engines for Sale: The Most Rebuilt CAT Engine in Heavy Industry

The CAT 3406E holds a unique position in the history of heavy diesel engines. Produced from 1993 through to the early 2000s as the successor to the 3406B, the 3406E combines the proven mechanical architecture of the 3406 family with electronic fuel injection management, delivering the reliability and longevity that made the 3406 family legendary, with the fuel efficiency and power output improvements of electronic control.

Key specifications and applications for the 3406E platform:

• Displacement — 14.6 litres, six-cylinder inline configuration
• Output range — 310 to 550 horsepower across the 3406E model range, depending on injection specification and rating
• Serial number prefixes — 1LW, 2WS, 4CK, 5DS, 6TS, 7CZ, each prefix confirming a specific build specification that determines internal component compatibility on a rebuild or replacement
• Applications — large excavators, heavy haulage trucks, articulated trucks, motor graders, wheel loaders, generator sets, and marine applications across decades of global heavy equipment production

Available from Imara Engineering as used, reconditioned, and rebuilt units, all serial numbers confirmed with full documentation.

CAT 3306 Engines for Sale: The Legacy Platform with Global Support

The CAT 3306 is one of the most widely produced diesel engines in Caterpillar's history, a naturally aspirated and turbocharged 10.5-litre six-cylinder platform that powered generations of excavators, dozers, motor graders, wheel loaders, and industrial plant equipment across every major market globally from the 1970s through to the 1990s. Decades after production ceased, the 3306 remains in active service across an enormous global install base, and demand for used and rebuilt 3306 engines remains consistently high among operators maintaining older heavy plant fleets where the 3306's proven reliability and strong global parts availability make it the most cost-effective powerplant option.

Key specifications and applications:

• Displacement — 10.5 litres, six-cylinder inline configuration in both naturally aspirated and turbocharged variants
• Applications — CAT D6, D7, and D8 dozers, CAT 14 and 16 motor graders, CAT 950 and 966 wheel loaders, CAT 225 and 235 excavators, and a broad range of generator and industrial power applications
• Parts availability — among the strongest global parts support networks of any legacy diesel engine, with rebuild components available from both OEM and aftermarket suppliers worldwide

Available from Imara Engineering as used, reconditioned, and rebuilt units with strong global shipping capability.

CAT 3208 Engines for Sale: The Versatile V8 Platform

The CAT 3208 is a 10.4-litre V8 diesel engine, a configuration unique among Caterpillar's inline-dominant engine family that powered an unusually broad range of applications across its production life, from excavators and agricultural equipment to marine vessels and generator sets. The V8 configuration gave the 3208 a compact physical footprint that made it suited to installations where an inline-six would not physically fit, and the platform's versatility created a global install base that sustains strong ongoing demand for replacement engines and components.

Key applications and variants:

• Excavator and plant equipment — used across a range of CAT mid-size equipment applications where the 3208's compact dimensions were an installation advantage
• Marine applications — the CAT 3208 marine engine is one of the most widely used commercial marine diesel engines in its displacement class, with a global install base across workboats, fishing vessels, and commercial craft
• Generator sets — widely deployed as a prime and standby power source in industrial and commercial generator applications

Available from Imara Engineering as used, reconditioned, and rebuilt units, including marine-specification variants for the 3208 platform.

CAT Engine Components: Supporting Your CAT Rebuild from Imara Engineering

Beyond complete engine assemblies, Imara Engineering's full Engine Parts range covers every internal component required to support a Caterpillar engine rebuild, so operators choosing to overhaul their existing engine rather than replace it as a complete assembly can source every component from the same specialist supplier.

Key Caterpillar engine components available from Imara Engineering:

• Cylinder Heads — pressure-tested OEM-grade cylinder heads for CAT C7, C9, C12, C13, C15, C15 ACERT, 3116, 3126, 3306, 3406, and 3406E. Check our Cylinder Heads range for full CAT platform coverage
• Gasket Kits and Rebuild Kits — complete overhaul kits for CAT C7, C12, C13, C15, C15 ACERT, 3306, 3406, 3406B, and 3406E. Check our Gasket Kits range for a consolidated rebuild supply
• Pistons and Rings — OEM-grade piston and ring sets for CAT C15, C15 ACERT, 3306, 3406, 3406B, 3406E, and 3208. Check our Pistons and Rings range for matched platform coverage
• Crankshafts — precision-ground crankshafts for CAT C15, C16, C18, 3406, 3406B, and 3406E with full journal dimension documentation. Check our Crankshafts range for full platform coverage
• Camshafts — OEM-specification camshafts for CAT C15, C15 ACERT, and 3406B with confirmed lobe geometry and duration specifications. Check our Camshafts range for C15 ACERT specific coverage
• Water Pumps, Oil Pumps, Alternators, and Starter Motors — full ancillary component coverage across the CAT engine range. Check our Engine Parts range for a complete component supply

Contact our team with your engine serial number and the component you require. We can confirm availability and consolidate all rebuild components into a single order.

Why Source Your Caterpillar Engine from Imara Engineering?

Operators and fleet managers across Australia, North America, Canada, and globally choose Imara Engineering for Caterpillar engines because a CAT engine replacement is not a catalogue decision; it is a precision engineering and operational commitment that determines how reliably and for how long your machine performs before the next major intervention.

• Full CAT Model Coverage — C7, C9, C12, C13, C15, C15 ACERT, C16, C18, 3208, 3116, 3126, 3306, 3406, 3406E, and 3406B, the complete Caterpillar diesel engine range is covered across used, reconditioned, and rebuilt condition grades
• OEM-Equivalent Quality — Every rebuilt and remanufactured Caterpillar engine is assembled to OEM dimensional and performance specifications. Rebuilt means verified engineering integrity, not a compromise on the standards your machine was designed around
• Serial Number Confirmed Fitment — Machine serial number, engine serial number prefix, ancillary configuration, and mounting arrangement are all cross-referenced before every engine ships. C15 or C15 ACERT, 3406E or 340, the correct specification confirmed before dispatch, not assumed
• Full Rebuild Documentation — Every engine dispatched by Imara Engineering includes complete build records, component replacement specifications, and test data — giving your workshop the documentation they need before the engine hits the stand
• Complete Component Supply — Cylinder heads, gasket kits, pistons, crankshafts, camshafts, water pumps, and rebuild components available alongside your Caterpillar engine in a single consolidated order
• Fast Worldwide Shipping — We dispatch Caterpillar engines to Australia, the United States, Canada, and internationally, professionally packaged for freight with full tracking from dispatch to delivery