Catalytic Converter for Infiniti FX35 (2009-2012) 3.5L

Direct-Fit Stainless Catalytic Converter Pair for 2009-2012 Infiniti FX35 (S51)

What it Does: This direct-fit catalytic converter pair replaces both factory banks on the 2009-2012 Infiniti FX35 (S51) powered by the VQ35HR 3.5L V6 to restore proper exhaust flow and emissions conversion.

The Stock Infiniti FX35 Catalytic Converter Failure

High-mileage S51 chassis vehicles equipped with the high-revving VQ35HR 3.5L V6 subject their dual-stage exhaust converters to severe thermal cycling and heat soak. Over time, oil consumption, rich fuel trims, or ignition misfires overheat the factory ceramic substrate, causing the precious-metal washcoat to degrade or the core to fracture internally. Once the honeycomb breaks apart, downstream oxygen sensors detect oxygen storage loss and trigger P0420 or P0430 catalyst efficiency faults while broken chunks choke exhaust flow.

Common Symptoms of a Failing OEM Catalytic Converter

• Check Engine Light: Triggers P0420 or P0430 catalyst efficiency fault codes.
• Metallic Rattle: Broken ceramic substrate rattling inside the housing on startup or deceleration.
• Power Loss & Failed Smog: Elevated exhaust backpressure, sluggish throttle response, and failed emissions inspections.

The Direct-Fit Stainless Exhaust Solution

This paired replacement restores both exhaust banks simultaneously using corrosion-resistant stainless steel bodies (8-inch length, 5-inch height) and mandrel-matched factory flange geometry. Each pipe houses a two-stage ceramic honeycomb substrate coated with a precious-metal washcoat engineered to convert HC, CO, and NOx efficiently under VQ35HR operating temperatures. Precision-located post-catalyst oxygen sensor bungs and factory mounting brackets ensure a leak-free, bolt-on installation with no cutting or welding required.

What's Included

• 2 x Catalytic Converter Pipes (Pair)
• 2 x 2-Bolt Flange Gaskets
• 2 x Ring Gaskets
• 6 x Bolts

Technical Specifications

Compatibility

• Infiniti FX35 (2009, 2010, 2011, 2012) — 3.5L V6 (S51)
• Excludes 2003-2008 FX35 (S50) and FX50 5.0L V8 models

Frequently Asked Questions & Fitment Warnings

Does this fit the S51 FX35?

Yes. This is a direct fit for the 2009-2012 Infiniti FX35 equipped with the VQ35HR 3.5L V6 engine. Excludes 2003-2008 FX35, FX50 5.0L V8, and CARB-regulated states (CA, NY, CO, ME).

Will this clear P0420/P0430 codes, and are O2 sensors included?

Yes, when caused by a worn catalyst. Replacing both banks resolves P0420/P0430 codes if no exhaust leaks exist; transfer your existing O2 sensors or install new ones.

Are gaskets and mounting hardware included?

Yes. Flange gaskets, ring gaskets, and bolts are included; soak seized fasteners with penetrating oil and torque evenly after cooling.

The Infiniti Performance Standard

Engineered for the S51 platform, this dual-bank converter restores factory exhaust flow efficiency and crisp VQ35HR throttle response. Precision flange alignment ensures leak-free sealing and reliable OBD-II readiness.