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If your Infiniti G35 is running poorly, swapping the catalytic converter can restore exhaust flow and emissions control. Choosing the right converter matters because fitment, emissions effectiveness, and durability all affect drivability and long-term compliance. This guide highlights the top shortlisted Infiniti G35 catalytic converter options selected for accurate fit, emissions performance, and build quality. Below you will find a concise evaluation of what we considered and why these units made the list, followed by practical factors to help you decide.
Looking for other parts? See all Infiniti G35 parts & accessories.
Top Picks at a Glance
| Best Reviewed A top-rated pick with lots of positive feedback | Anytek Catalytic Converter for Infiniti G35/G37/Q50/Q60 and Nissan 3.5–3.7L Applications |  |
| Most Popular A crowd favorite that many people choose with confidence | MAYASAF 2" Universal Catalytic Converter — 2-Pack with O2 Port & Heat Shield |  |
| Best Quality Built to a higher standard if you want something more solid | RILONH Front Catalytic Converters for Infiniti G37 3.7L (Left + Right) |  |
| Best Budget The cheapest option that still gets the job done reliably | ASOPARTS 2.25" Universal Catalytic Converter with O2 Port (pair) |  |
| Most Sold A high-volume bestseller chosen again and again | ZCATAPARTS Catalytic Converters for Infiniti G35/G37/EX35/FX35/FX37/M35/M37 and Nissan 350Z/370Z (EPA Compliant) |  |
| Best Value for Money The sweet spot between price and what you get | FOMIUZY 2.25" Universal High-Flow Catalytic Converter (2-pack) |  |
| Best Overall The best all-around choice for most situations | PHILTOP Catalytic Converter for Infiniti G35/G37 and select 3.5/3.7L models |  |
1. Anytek Catalytic Converter for Infiniti G35/G37/Q50/Q60 and Nissan 3.5–3.7L Applications
| Manufacturer | Anytek |
|---|---|
| Manufacturer Part Number | 10080147-ANK |
| OEM Part Number | 644029, 41096, 17115, 644030, 41097, 17116 |
| Special Features | 1-year warranty; manufactured to original standard; restricted in CA, CO, NY, ME |
This Anytek catalytic converter is a replacement unit built to the original-fit standard for Infiniti 3.5–3.7L applications and intended to restore emissions control and drivability after a failed converter. It installs in place of the factory unit and is commonly used during emissions repairs or when correcting P0420/P0430 fault codes. Notable features include a 409L stainless steel shell for corrosion resistance and high-temperature welding for durability, plus compatibility with many Infiniti G35 and G37 model years listed by the manufacturer. Buyers will find it useful for returning a car to compliant emissions operation without sourcing an OEM unit. Important limitations are state restrictions: it is not legal for sale or use in California, Colorado, New York, or Maine due to emissions regulations, and some buyers reported minor fitment adjustments or clearance tweaks during installation. The product comes with a one-year warranty and may require light modification or professional installation to ensure proper exhaust routing and clearance.
Best for: A reliability-focused buyer who needs a straightforward factory-quality replacement to restore emissions compliance and avoid recurring fault codes on their Infiniti, prioritizing proven function over aftermarket performance upgrades.
Less Ideal for: Drivers in states with strict emissions rules or owners seeking a performance-oriented or custom exhaust solution should consider other options or state-compliant parts.
- Made to original factory standards for direct replacement on listed Infiniti models
- 409L stainless steel shell and high-temperature welding for corrosion and heat resistance
- Helps resolve emissions faults and pass inspections when used outside restricted states
- Includes a one-year warranty and manufacturer support
- Not legal for sale or use in California, Colorado, New York, or Maine due to state emissions rules
- May need minor adjustments or welding for perfect fitment on some vehicles
Verdict A practical, factory-standard replacement for Infiniti 3.5–3.7L models that restores emissions function affordably, but it is not legal for use in several states.
2. MAYASAF 2" Universal Catalytic Converter — 2-Pack with O2 Port & Heat Shield
| Inlet/Outlet | 2 inches ID |
|---|---|
| Overall length | 13 inches |
| Certification | EPA federal standard |
These MAYASAF universal catalytic converters are sold as a two-pack designed for 2-inch inlet/outlet exhaust systems and include a bung for an oxygen sensor plus a partial heat shield. For an Infiniti G35 owner looking for a convenient, budget-friendly replacement, they serve as a DIY-friendly option that can be cut and welded into an existing exhaust. The internal honeycomb has larger holes than many factory units, which reviewers report improves flow and can give slightly better fuel economy and responsiveness but may increase exhaust note. The included O2 port lets you maintain the factory sensor location on G35 applications that use a single sensor in that section, though some G35 model years have different sensor counts or positions so fit should be verified. Installation will typically require cutting, welding, and orientation of the heat shield, so a shop or basic fabrication skills are recommended. These are EPA federal certified for aftermarket use, making them a legal option in states that allow aftermarket converters, but they are not intended for states with additional local restrictions.
Best for: Convenience-driven Infiniti G35 owners who want an affordable, ready-to-fit aftermarket converter they can have installed quickly or swap in during a DIY exhaust repair.
Less Ideal for: Owners who need an exact factory-location direct-fit converter for emissions testing in restricted states or who want a quiet, factory-sound replacement without any exhaust modification.
- Universal 2-inch inlet/outlet fits common exhaust pipe sizes after cutting or adaptors
- Built-in O2 sensor bung preserves factory sensor placement where applicable
- Includes a heat shield to protect nearby components
- Sold as a two-pack so you can replace multiple sections or keep a spare
- Universal design may not match exact sensor count or placement on all G35 model years
- Requires cutting and welding for installation, not a direct bolt-on replacement
- Flow-through internal structure can increase exhaust noise compared with factory units
Verdict A cost-effective universal replacement for G35 owners wanting a quick aftermarket fix, provided you accept welding and possible changes in exhaust tone.
3. RILONH Front Catalytic Converters for Infiniti G37 3.7L (Left + Right)
| Fitment | Infiniti G37 3.7L 2008-2013 |
|---|---|
| Placement on Vehicle | Front, Left and Right |
| Substrate Material | Ceramic |
| Heat Shield Material | Stainless Steel |
These are a matched left and right pair of front catalytic converters built for the 3.7L V6 Infiniti G37. They replace the factory front converters and arrive with installation gaskets and bolts so you can complete the swap without reusing old hardware. The housings are heavy-duty stainless steel and the substrate is ceramic, which supports good oxygen storage and corrosion resistance for durability under normal driving. Typical use is a direct replacement after converter failure or to restore emissions function and clear a check-engine light. Practical benefits include complete hardware in the box and construction aimed at long service life, plus straightforward bolt-on fitment for the stated model years. Important limitations are regulatory: the units are EPA compliant but not CARB compliant, so they cannot be used where California-style emissions parts are required, and they may produce an initial odor on first startup. Installation may require about an hour per side for a competent DIYer or a standard shop labor job.
Best for: Performance-oriented buyers who want a durable, factory-style replacement to restore exhaust and emissions function on a 3.7L Infiniti while keeping drivability and engine management stable.
Less Ideal for: Buyers in states that require CARB-compliant parts or those seeking a high-flow performance converter for increased horsepower should look for alternatives.
- Sold as a matched left and right front converter pair for the G37 3.7L so both sides are replaced consistently.
- Includes installation hardware and gaskets to avoid reusing worn parts.
- Stainless steel housing with ceramic substrate for durability and reliable emission control.
- Designed for direct bolt-on fitment to the listed Infiniti model years, simplifying replacement.
- Not CARB compliant so not legal for use in states that require CARB-certified parts.
- May emit a temporary odor on first startup after installation.
Verdict A durable, bolt-on matched front converter pair aimed at restoring emissions and drivability for the G37 3.7L, but not legal where CARB-certified parts are required.
4. ASOPARTS 2.25" Universal Catalytic Converter with O2 Port (pair)
| Inlet/Outlet | 2.25" |
|---|---|
| Overall Length | 11" |
| Includes | O2 sensor ports (pair) |
These ASOPARTS converters are a budget-focused universal replacement sold as a pair and intended to restore catalytic function or serve as interim high-flow pieces. They install in-line where a 2.25-inch inlet and outlet match the exhaust piping and include O2 sensor bungs so factory sensors can be reused. The stainless/aluminized shell and honeycomb ceramic substrate aim to resist heat and corrosion while keeping weight and cost down. In practice they work well when pipe adapters or minor cutting is used to fit differing exhaust runs, and many buyers report straightforward installation and usable emissions performance. Limitations are typical for universal cats: internal quality can vary, fitment may need additional plumbing or welding, and a few users report premature rattling or insufficient catalytic activity that can trigger check engine lights. For an Infiniti G35 this converter is a stopgap or budget repair when matched to the car's exhaust diameter, but it is not a guaranteed direct factory-replacement fit and may require a shop to adapt and verify emissions compliance.
Best for: Budget-conscious owners looking for an affordable catalytic solution for basic repairs or temporary replacement while prioritizing cost over factory-exact fitment and long-term durability.
Less Ideal for: Drivers seeking a factory-quality, plug-and-play direct replacement for an Infiniti G35 or those who need guaranteed emissions certification should consider vehicle-specific factory-quality converters instead.
- Includes O2 sensor ports so original sensors can be re-used
- Stainless/aluminized shell offers basic corrosion and heat resistance
- Sold as a pair for both sides or front/rear swaps
- Universal design fits many exhaust systems with simple piping or adapters
- Universal sizing often requires cutting, adapters, or welding for proper fit
- Quality and internal packing appear inconsistent between units
- Not guaranteed to clear emissions codes on all vehicles without tuning or verification
Verdict A low-cost, universal pair that can get an Infiniti G35 back on the road cheaply but may need plumbing work and offers variable long-term performance.
5. ZCATAPARTS Catalytic Converters for Infiniti G35/G37/EX35/FX35/FX37/M35/M37 and Nissan 350Z/370Z (EPA Compliant)
| Brand | ZCATAPARTS |
|---|---|
| Model | YFND-ZY |
| Compatible engines | 3.5L and 3.7L V6 (listed Infiniti/Nissan models) |
| EPA status | EPA compliant for federal emissions vehicles |
This ZCATAPARTS catalytic converter is built as a direct replacement for the front/rear converter assemblies used on 3.5L and 3.7L Infiniti and Nissan V6 models. It uses stainless steel construction and is sold as a vehicle-specific unit intended to restore exhaust flow and emissions control when an original converter is clogged or damaged. Typical use is straightforward replacement during exhaust repair or restoration on compatible G35/G37/EX35/FX35/FX37/M35/M37 and 350Z/370Z models. The listing highlights EPA compliance for federal emissions vehicles and claims corrosion and heat resistance from the stainless materials, which should help longevity compared with cheaper stamped parts. Buyers report the parts slide into place and work to clear engine codes caused by clogged converters, though one review noted a fitment variance on a left-side unit that required attention. Installation generally requires standard exhaust hardware and basic mechanical skills or a shop. This is a practical factory-replacement option for restoring emissions performance, but confirm fitment and expect professional installation if you lack exhaust experience.
Best for: Practical, risk-averse buyers who want a vehicle-specific, factory-replacement style catalytic converter to restore emissions function without experimenting with universal or performance aftermarket options.
Less Ideal for: Buyers in states that enforce stricter emissions rules or those seeking a high-performance or pre-tuned aftermarket converter should look for alternatives designed for those needs.
- Vehicle-specific fit for many Infiniti and Nissan 3.5L/3.7L V6 models, simplifying replacement.
- Stainless steel construction for improved corrosion and heat resistance versus basic stamped units.
- Sold as an EPA-compliant option for federal emissions-equipped vehicles.
- Reports of clean packaging and complete parts, reducing installation surprises.
- Not legal for sale or use in several states with stricter regulations including California, Colorado, New York, and Maine.
- One customer reported a slight fitment mismatch on a left-side unit, so individual inspection and potential adjustment may be required.
Verdict A practical, stainless-steel, vehicle-specific replacement catalytic converter suited for restoring emissions performance on compatible Infiniti and Nissan V6 models, provided you confirm fitment and local legality.
6. FOMIUZY 2.25" Universal High-Flow Catalytic Converter (2-pack)
| Inlet/Outlet | 2.25" |
|---|---|
| Quantity | 2 catalytic converters |
| Exterior | Milled stainless/aluminized body |
| Overall Length | 13" |
This universal 2.25-inch catalytic converter kit is designed as a direct-replacement front cat for vehicles with a matching 2.25" inlet/outlet and includes two units. It is typically used to replace a failed or stolen front catalytic converter and to clear a P0420 code when the vehicle has the correct pipe size. The unit features a stainless steel aluminized body and a double-layer ceramic carrier intended to increase flow and surface area for improved exhaust flow and fuel economy. Installation is straightforward for someone experienced with exhaust work but the listing recommends tacking then welding the joints for best sealing. Practical benefits include lower cost compared with factory replacements and a lifetime warranty claim offered by the seller. Important limitations for Infiniti G35 owners: this is a universal part, so fitment can vary and some buyers report mismatched diameters or missing O2 sensor bungs, and aftermarket catalysts of this cost can show variable long-term durability and emissions performance compared with higher-end factory-quality replacements.
Best for: Practical optimizers who prioritize saving money on maintenance while accepting some DIY fitting and welding work to return an Infiniti G35 to clean-running condition.
Less Ideal for: Buyers who need a guaranteed vehicle-specific, emissions-certified factory-quality replacement or who want a plug-and-play OEM-equivalent part without any exhaust modification.
- Sold as a two-pack for replacement of both sides or a spare
- Stainless steel/aluminized body resists rust better than plain steel
- Double-layer ceramic carrier aimed at higher flow and increased surface area
- Simple direct-fit style allows welding or clamp installation for quick replacement
- Universal sizing can be inconsistent so inner or outer diameters may not match G35 exhaust piping exactly
- May lack a welded O2 sensor bung depending on the unit, requiring additional fabrication
- Lower-cost internal substrate may degrade faster than premium factory-quality converters under heavy use
Verdict A cost-conscious universal option for G35 owners who can verify 2.25" pipe fitment and are prepared to weld or modify for a reliable budget replacement.
7. PHILTOP Catalytic Converter for Infiniti G35/G37 and select 3.5/3.7L models
| Brand | PHILTOP |
|---|---|
| Model fitment | Infiniti G37 2009-2013; compatible with G35 and select 3.5/3.7L models |
| Manufacturer Part Number | 8623EXP3164US |
| OEM Part Numbers replaced | 644029, 41096, 644030, 41097 |
This PHILTOP catalytic converter replaces factory catalytic units for compatible Infiniti 3.5/3.7L models and is intended to restore emissions control and normal exhaust sound. It uses a stainless steel housing with welded seams and an internal honeycomb ceramic substrate treated with precious metal catalysts to clean exhaust gases while offering a high-flow design that aims to keep engine output steady. Installation typically involves unbolting the old unit and fitting this converter in its place; some buyers report the fit is straightforward on Infiniti applications but others needed minor adjustments or professional help. The unit is EPA compliant for most states outside strict California/Colorado rules and is marketed as rust resistant for longer service life. Expect quieter operation and improved emissions readings if your original converter is failing, but verify flange orientation and mounts before installation since fitment variations have been reported and heat shields or mounting tabs may require reuse or modification.
Best for: A balanced all-round buyer who wants a factory-style replacement to restore emissions performance and drivability on an Infiniti G35 without prioritizing premium OEM pricing or exotic performance parts.
Less Ideal for: Not ideal for buyers who need California-compliant converters or those seeking a plug-and-play unit guaranteed to include all factory heat-shield mounts and exact flange geometry without any adjustment.
- Designed for Infiniti 3.5/3.7L applications to replace worn converters
- Stainless steel construction and welded seams for corrosion resistance
- High-flow ceramic substrate aimed at maintaining engine performance
- EPA compliant for aftermarket use in supported states
- Reported to reduce exhaust noise and clear certain check-engine codes
- May require minor modifications or professional installation for correct flange alignment or heat-shield mounting
- Not legal for sale or installation in some states with stricter emissions rules
- Fitment reports vary by model year so confirmation before purchase is recommended
Verdict A cost-effective, high-flow factory-replacement catalytic converter for Infiniti 3.5/3.7L models that restores emissions and reduces noise if you confirm fitment and are prepared for minor installation adjustments.
Choosing the Right Infiniti G35 Catalytic Converter: Key Factors to Consider
Fitment and Compatibility
Exact fitment to the Infiniti G35’s exhaust flanges and hangers is essential because converters that do not match mounting points add installation time and may require additional modifications. A converter designed for the G35 will align with oxygen sensor locations and flange thicknesses, reducing the risk of exhaust leaks.
Poor fit can increase labor costs and lead to gasket or seal failures. Confirming bolt pattern, inlet and outlet diameters, and overall length helps ensure a straightforward installation and correct exhaust geometry, which preserves drivability and prevents unwanted stresses on adjacent components.
Substrate Type and Emissions Performance
The substrate inside the catalytic converter—the honeycomb monolith and washcoat—determines how efficiently it converts pollutants. Higher cell density and appropriate precious metal loading typically improve conversion of hydrocarbons, carbon monoxide, and nitrogen oxides, which directly affects exhaust emissions compliance.
Consider how the substrate handles thermal cycling and potential clogging. A robust substrate resists degradation from contaminants and maintains conversion efficiency over time, which is important for passing emissions checks and maintaining engine performance.
Flow Characteristics and Backpressure
Flow path design influences backpressure, which can impact engine breathing and throttle response. A converter that is too restrictive can reduce power and fuel efficiency, while one with overly large passages may not achieve optimal emission conversion at normal operating temperatures.
Balance is key: choose a unit engineered to provide sufficient flow for the G35’s engine displacement while retaining enough catalyst surface area to meet emissions goals. Consider how the design affects warm-up time and conversion efficiency at typical operating loads.
Thermal Management and Durability
Catalytic converters operate at very high temperatures, so housing materials, insulation, and heat shielding matter for longevity. Corrosion-resistant housings and quality welds protect the unit from road salts and moisture, while thermal barriers help maintain catalyst operating temperature and prevent premature failure.
Durable construction also helps the converter survive vibration and road shock. Look for features that reduce the risk of substrate damage during thermal expansion and contraction to extend service life and reliability.
Oxygen Sensor Access and Integration
Proper oxygen sensor placement is important for accurate engine control and emissions regulation. A converter must provide correct sensor bungs or ports located at the expected distances from the engine so the vehicle’s engine control unit reads accurate exhaust composition.
Ease of access for sensor replacement and secure bung fitment reduce the potential for exhaust leaks and misreads. Confirm that sensors can be installed without interference from heat shields or surrounding components to maintain reliable operation.
Warranty and Support
Warranty terms reflect a manufacturer’s confidence in the converter’s materials and workmanship. A clear warranty covering defects and premature failures provides reassurance and can reduce long-term ownership risk.
Also consider the availability of technical documentation and installation guidance. Good support makes installation smoother and helps address concerns like torque specs, gasket selection, and any recommended break-in practices.
FAQ
How do I know if my Infiniti G35 catalytic converter is failing?
Symptoms often include a noticeable drop in engine performance, reduced acceleration, or a rotten egg smell from the exhaust. You may also see persistent engine misfires or reduced fuel economy. Many failures produce a noticeable change rather than a sudden fault, so monitoring these signs can help you decide when to inspect the converter.
Will a bad catalytic converter trigger the check engine light on an Infiniti G35?
Yes, issues with the catalytic converter frequently trigger the check engine light when oxygen sensor readings indicate poor conversion efficiency. Trouble codes related to catalyst efficiency or oxygen sensor performance are common. Diagnosing the exact code helps determine whether the converter itself or a related sensor or exhaust leak is the root cause.
Can I replace the catalytic converter on an Infiniti G35 myself?
Replacing the catalytic converter is possible for someone with moderate mechanical skills and the right tools. It typically involves lifting the vehicle, unbolting flanges or cutting old sections, and fitting the new unit. Be prepared to address rusted hardware or tight clearances, and follow torque specs and oxygen sensor procedures to ensure a correct installation.
How does a catalytic converter affect exhaust emissions on an Infiniti G35?
The converter reduces pollutants by catalyzing chemical reactions that convert hydrocarbons, carbon monoxide, and nitrogen oxides into less harmful substances. A functioning unit is central to keeping tailpipe emissions within regulatory limits and maintaining the intended operation of the engine control system.
What should I check before buying a replacement catalytic converter for an Infiniti G35?
Verify exact fitment for the G35, including flange type, inlet and outlet diameters, and oxygen sensor port locations. Also check the substrate description and housing materials for durability, and review warranty coverage. Confirming these details minimizes installation surprises and supports long-term performance.
How We Chose the Best Infiniti G35 Catalytic Converter
We focused on units designed specifically for the Infiniti G35 and evaluated them against criteria that matter to owners. Key filters included fitment accuracy to factory exhaust flanges and mounting points, verified substrate type and coating for emissions performance, and durability features like housing construction and weld quality. We also considered airflow characteristics that affect backpressure and engine response, as well as thermal management and heat shielding to reduce heat-related failures. Finally, we reviewed documented installation considerations and available warranty coverage to gauge long-term value. Units that lacked clear fitment information, definitive substrate details, or adequate thermal protection were excluded. The result is a list of converters that meet core expectations for emissions control, mechanical compatibility, and reliable service life for the Infiniti G35.
Our full evaluation process is outlined in our review methodology.
Conclusion
Choosing the right catalytic converter for an Infiniti G35 is about matching fitment and emissions capability to the car’s needs. Prioritize converters that specify correct flange and sensor locations, a durable housing, and an appropriate substrate that balances flow and conversion efficiency.Weigh the tradeoffs between flow and catalyst surface area, and consider thermal protection and warranty when assessing long-term value. Focusing on these criteria will help you restore emissions control and reliable exhaust performance.
Explore More:
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