2003-2006 Infiniti FX45 M45 JDM 4.5L V8 Engine VK45DE Motor OEM

Eliminate engine knock, oil consumption, and low oil pressure issues with this premium JDM 2003-2006 Infiniti FX45 M45 4.5L V8 Engine. Imported directly from Japan, this genuine OEM VK45DE power plant serves as the ultimate low-mileage direct replacement for your worn or failed domestic engine block. Hand-selected from clean Japanese donor vehicles, these JDM units have significantly fewer miles (approximately 45k–60k) compared to domestic high-mileage salvage options. Featuring an aluminum block construction, double overhead camshafts (DOHC), and continuous variable valve timing, this authentic JDM V8 engine restores smooth idling, original luxury horsepower, and robust torque output to your premium Infiniti vehicle.

Vehicle Specifications

• Year Range: 2003, 2004, 2005, 2006

• Make & Model: Infiniti FX45 & Infiniti M45 (S50 & Y34 / Y50 Chassis Series)

• Engine Code: VK45DE (4.5L V8 Architecture)

• Displacement: 4.5 Liters (4494 cc)

• Engine Type: 32-Valve DOHC V6 (Dual Overhead Cam V8 Layout)

• Fuel Delivery: Sequential Multi-Port Electronic Fuel Injection (SEFI)

• Origin: Japan (Genuine OEM Japanese Domestic Market Import)

• Condition: Premium Used Import (Inspected, cleaned, and compression/leak-down tested)

• Mileage: Approx. 45,000–60,000 miles (Low Japanese domestic usage)

Vehicle Fitments

• Direct US-Spec Replacement:

  • 2003-2006 Infiniti FX45 AWD Luxury Crossover SUV

  • 2003-2004 Infiniti M45 Sedan (Y34 Chassis)

  • 2006 Infiniti M45 Sedan (Y50 Chassis)

• Interchange Note: Designed strictly for vehicles originally equipped with the 4.5L VK45DE engine option. Will not interchange with FX35 or M35 models running V6 platforms without a complete custom wiring harness and computer conversion.

Included Parts

• VK45DE Longblock: Complete Aluminum Block, Cylinder Heads, Valve Covers, and Lower Oil Pan Assembly

• Intake Manifold: Factory lower and upper intake manifold plenum with fuel rail and injectors

• Sensors: Camshaft position sensors, crankshaft position sensor, knock sensors, and oil pressure switches

• Pulleys & Assemblies: Factory crankshaft harmonic balancer pulley and water pump assembly

• Exhaust Manifolds: Original cast-iron exhaust manifold headers (left and right sides)

Installation & USDM Drop-In Notes

• Component & Accessory Swapping (Crucial): While the core structural block internals, pistons, and cylinder heads are 100% identical, installers must transfer the original US-spec outer engine wiring harness, oil pan configuration (depending on AWD vs. RWD crossmember clearance requirements), external accessories (alternator, starter, power steering pump, A/C compressor), and the electronic throttle body to ensure a direct plug-and-play match with your vehicle's factory ECU computer.

• Oil Priming Requirement: Prior to your first startup, it is highly recommended to manually prime the oil pump and engine oiling system to ensure proper lubrication across the complex quad-cam valvetrain layout. Refill exclusively with high-quality full synthetic motor oil and a fresh OEM oil filter.

• Preventative Maintenance: To safeguard your repair investment and eliminate the risk of oil leaks, it is strongly advised to replace the front crank seal, rear main seal, valve cover gaskets, spark plug tube seals, and the thermostat while the engine is separated from the transmission bellhousing.