Infiniti Parts Guide: Common Failures, Reliable Components & OE Replacement Tips
Introduction
Infiniti, Nissan’s luxury division, has built a strong reputation for blending high-performance engineering with premium comfort. Powered largely by the legendary VQ and newer VR engine families, these vehicles deliver exceptional driving dynamics. However, maintaining that performance requires strict adherence to maintenance schedules and using high-quality components.
When repairing an Infiniti, part quality is non-negotiable. Because these vehicles utilize tightly toleranced engine internals and complex electronic management systems, cheap aftermarket alternatives often trigger check engine lights or fail prematurely. Sourcing genuine Infiniti OE parts or OEM-equivalent components ensures your G37, Q50, or QX60 retains its factory-level reliability and performance.
Parts That Commonly Fail on Infiniti Vehicles
- Valve Cover Gaskets & Spark Plug Tube Seals: (VQ35DE & VQ37VHR engines - G35, G37, FX35). The intense heat generated by these V6 engines causes the rubber gaskets to harden and crack over time. This leads to oil leaking into the spark plug tubes, which can short out ignition coils. OE-quality gaskets are crucial because aftermarket rubber compounds often degrade quickly under VQ heat cycles.
- Timing Chain Tensioners and Guides: (Early VQ35DE engines - 2003-2007 G35/FX35). The plastic timing chain guides are prone to premature wear, causing a distinct rattling noise. If ignored, the chain can jump timing. Replacing these with updated Infiniti replacement parts ensures the use of redesigned, reinforced plastics that resist oil degradation.
- Turbocharger Wastegate Actuators: (VR30DDTT engines - Q50, Q60 3.0t). The electronic wastegate actuators on the twin-turbo 3.0L engines can bind or fail, leading to underboost codes (P0234/P0299). Using OE replacements guarantees correct electronic calibration with the Engine Control Module (ECM).
- Serpentine Belt Tensioner Pulleys: (VR30DDTT engines). The bearings inside the tensioner pulleys are known to fail, causing belt squeal or catastrophic belt shredding. OE tensioners use high-grade Japanese bearings (like NSK or NTN) that withstand the specific belt loads of the VR engine.
- Camshaft Position Sensors: (Most VQ-powered models). These sensors frequently fail due to thermal cycling, causing stalling or hard-starting issues. Always use OE Hitachi or Denso sensors; cheap aftermarket sensors have incorrect voltage outputs that the Infiniti ECM will reject.
Parts Known for Exceptional Quality on Infiniti Vehicles
- VQ-Series Engine Blocks & Internals: The VQ35 and VQ37 engines are globally recognized for their bulletproof bottom ends. Featuring microfinished forged steel crankshafts and molybdenum-coated pistons, these engines routinely surpass 200,000 miles with basic oil changes.
- 7-Speed Automatic Transmissions (RE7R01A): Manufactured by Jatco (a Nissan subsidiary), this transmission is exceptionally durable. It handles high-torque applications in both rear-wheel and all-wheel-drive configurations effortlessly, provided the fluid is serviced at proper intervals.
- OEM Exhaust Systems: Infiniti utilizes high-grade, thick-walled stainless steel for its factory exhaust manifolds and piping. Unlike many competitors, Infiniti exhaust systems rarely suffer from premature rust-through or weld failures, even in harsh winter climates.
Key OE Parts Buying Tips for Infiniti Owners
- Leverage Nissan Cross-Compatibility: Because Infiniti is a Nissan brand, many parts (like VQ engine sensors, filters, and suspension arms) are identical. Buying the Nissan-branded OE part can sometimes be cheaper than the Infiniti-boxed equivalent.
- Stick to OEM Electronics: Infiniti ECMs are notoriously picky. For mass airflow (MAF) sensors, oxygen sensors, and ignition coils, strictly buy OE brands like Hitachi, Denso, or NGK to avoid persistent check engine lights.
- Verify Fluid Specifications: Never use universal fluids. Infiniti transmissions require Nissan Matic-S or Matic-J fluid, and their cooling systems require Nissan Long Life Blue Antifreeze. Using incorrect fluids causes rapid seal and clutch degradation.
- Beware of Counterfeit Suspension Parts: Lower control arms and compression rods are common wear items on the G and Q series. Counterfeit parts flood the market with inferior rubber bushings. Always buy Infiniti OE parts from authorized, reputable e-commerce retailers.
Frequently Asked Questions
What parts fail most on Infiniti?
The most common Infiniti problems involve oil leaks from valve cover gaskets, failing camshaft position sensors, and worn suspension compression rod bushings. On newer turbocharged models (Q50/Q60), serpentine belt tensioners and turbo wastegate actuators are frequent failure points.
Are Infiniti parts expensive?
Infiniti parts are generally more affordable than European luxury brands like BMW or Mercedes-Benz, but slightly more expensive than standard Nissan parts. Sourcing OEM-equivalent parts from original suppliers (like Hitachi or KYB) is a great way to save money without sacrificing quality.
What is the most common Infiniti repair?
For VQ-powered models (G35, G37, QX60), replacing the valve cover gaskets and spark plug tube seals is the most common repair. This is a standard maintenance procedure usually required between 80,000 and 100,000 miles to prevent oil from damaging the ignition coils.
Conclusion
Infiniti vehicles offer an impressive balance of Japanese engineering and luxury performance. While their powertrains are fundamentally robust, heat cycling and electronic sensitivities mean that certain gaskets, sensors, and tensioners will eventually require replacement. By investing in genuine Infiniti OE parts and OEM-equivalent components, you protect your vehicle's intricate systems and ensure it continues to deliver the thrilling Infiniti reliability and driving experience you expect.