The Caterpillar 3408 engine is one of the most iconic V8 diesel platforms ever produced, known for delivering extreme torque, exceptional durability, and unmatched performance in heavy-duty applications. First introduced in the 1970s and produced through the early 2000s, the 3408 remains a preferred engine for repowers, restorations, and rebuilds thanks to its strong mechanical foundation and widespread aftermarket support. With its 18-liter displacement, twin-turbo options, and cast-iron block construction, the 3408 was built to handle punishing workloads—making it an ideal candidate for long-term operation even after OEM discontinuation. At Diesel Pro Power, we help keep thousands of these V8 workhorses in service with high-quality aftermarket parts, overhaul kits, and expert support trusted by over 40,000+ global customers. Engine Type: 4-stroke, V8 diesel engine Displacement: 18.0 liters (1,099 cubic inches) Bore x Stroke: 5.4 in x 6.5 in (137 mm x 165 mm) Aspiration: Naturally aspirated or turbocharged, depending on model Aftercooling: Available in jacket water aftercooled (JWAC) or air-to-air aftercooled (ATAAC) configurations Compression Ratio: Typically 14.5:1 Firing Order: 1-5-4-2-6-3-7-8 Horsepower Range: 440 HP to 900+ HP (marine and high-output models) Peak Torque: Up to 2,500 lb-ft depending on configuration Rated Speed: 1,800–2,300 RPM Idle Speed: 600–800 RPM Dry Weight: Approximately 3,600–4,000 lbs depending on setup Fuel Delivery: Mechanical direct injection system Pump Type: Inline or rotary mechanical injection pump Governor: Mechanical governor, adjustable for speed/load stability Fuel Type: Diesel No. 2 (ULSD-compatible with proper sealing) Oil Capacity: 10–16 gallons (depending on oil pan configuration) Oil System: Full-pressure system with gear-driven pump Cooling System: Liquid-cooled via gear-driven centrifugal pump Thermostat Operation: Dual-element, regulates between 180–200°F Starting System: 12V or 24V electric Alternator Options: Belt-driven, marine and industrial grades available Instrumentation: Analog gauges or upgraded aftermarket sensor kits While no longer produced by Caterpillar, the 3408 remains highly serviceable and cost-effective to rebuild thanks to its modular, all-mechanical design. At Diesel Pro Power, customers regularly source the following: Complete overhaul kits (liners, pistons, bearings, gaskets) Cylinder head assemblies (new or remanufactured) Turbocharger replacements (single or twin-turbo) Fuel injection system components (pumps, nozzles, fuel lines) Water and oil pumps for marine or stationary versions Gasket sets and sealing kits for major rebuilds or top-end refresh We offer marine-grade, industrial, and export-ready variants for multiple build types. Thanks to its raw torque and simplicity, the CAT 3408 has long served across multiple high-demand industries, and remains in active use where newer engines are too costly or complex to maintain. The 3408 is one of the most sought-after Caterpillar marine engines due to its torque-heavy profile and compatibility with both propulsion and auxiliary systems. Commercial Fishing Vessels – Ideal for long-range diesel fishing boats requiring reliability and low-speed torque Push Boats and Tugboats – Twin 3408 setups offer excellent maneuvering and load control Crew Boats and Work Barges – Common in offshore energy and support logistics Marine Generators – Used in auxiliary and hotel power configurations on larger ships Landing Craft and Utility Boats – Military and commercial variants frequently spec'd with CAT V8 power Diesel Pro Power stocks marinized components such as water-cooled manifolds, seawater pumps, and corrosion-resistant gaskets. The 3408's torque curve and rebuildability make it perfect for severe-duty operations across construction, mining, and oil & gas sectors. Power Generation Units – Used as prime movers in off-grid and backup generator sets Crushers and Grinders – High-torque operation perfect for continuous-load equipment Drilling Rigs – Powering rotary drives or hydraulic systems Pumps – Large-scale water transfer, flood control, or fracking operations Forestry Equipment – Found in mulchers, feller bunchers, and mobile wood processors Mud Pumps and Blenders – High-load equipment in fracking fields Flare Stack Compressors – Remote site operations requiring rugged, rebuildable diesel power Skid Power Units – 3408-powered generator or PTO sets for modular equipment Irrigation Pumps – Large diesel-powered pumps running off mechanical governors Heavy Tractors and Crawlers – Used in sugarcane and large-scale field operations, especially outside the U.S. Export Builds – Still in demand for agricultural machinery in Latin America, Africa, and Asia Despite the rise of newer emissions-compliant engines, the 3408 is still widely rebuilt and reinstalled in working fleets because: No ECM Required – Fully mechanical engine, ideal for remote or emissions-exempt regions Simple Diagnostics – No electronics or proprietary scan tools needed High Torque Output – Can replace multiple smaller diesels with one engine Rebuildable Design – Wet liners, reusable components, and modular heads Lower Cost of Ownership – Especially when maintained with quality aftermarket parts Diesel Pro Power makes it easy to keep these engines in service, whether you're running one unit or an entire fleet. We offer everything needed to overhaul, service, or maintain the Caterpillar 3408 engine:  Complete rebuild kits for marine, industrial, and generator variants  Water pumps, turbochargers, injectors, gaskets, and more  Support for both early and late serial ranges  In-stock inventory with fast global shipping  Technical support from diesel experts All parts are sourced to meet or exceed OEM performance, ensuring your 3408 runs as reliably as the day it was new. The Caterpillar 3408 is a prime example of old-school diesel engineering done right—high horsepower, ultra-durable, and easy to keep running with the right support. Whether you're operating a fishing vessel, managing industrial generators, or servicing equipment in the oilfield, the 3408 offers unmatched value when paired with aftermarket expertise. Diesel Pro Power helps keep these engines alive with the largest online catalog of 3408 replacement parts, trusted by professionals across marine, power, and industrial sectors. Marine CAT 3408 Component Maintenance Life
Parts for Caterpillar 3408
-
Select Parts Category
Loading...
Engine Specifications & Applications Of This Engine
Overview of the Caterpillar 3408 Engine
Technical Specifications of the Caterpillar 3408
Core Engine Configuration
Performance Ratings
Fuel System
Lubrication & Cooling
Electrical and Starting
Common Aftermarket Rebuild Focus for 3408 Engines
Applications of the Caterpillar 3408 Engine
Marine Applications
Industrial Applications
Oilfield & Energy
Agriculture & Land Management
Why the CAT 3408 Remains Relevant in the Aftermarket
Diesel Pro Power – Aftermarket Leader for CAT 3408 Engines
Conclusion
Additional Resources
The Legacy of the Caterpillar Marine 3408 Engine