Catalytic Converter for Lexus GX (2005-2009) 4.7L Front Left & Right

Direct-Fit Replacement Catalytic Converter Set for 2005-2009 Lexus GX (J120)

What it Does: The front left and right catalytic converter set replaces deteriorated factory manifold converters on the 2005-2009 Lexus GX to clear diagnostic trouble codes P0420/P0430 and restore factory exhaust velocity.

The Stock Lexus GX Manifold Substrate Degradation

The factory exhaust manifolds on the J120 platform feature integrated ceramic washcoats that endure intense thermal cycling from the 4.7L V8. Over time, high exhaust gas temperatures and carbon accumulation degrade the precious metal washcoat, causing washcoat sintering and structural thermal fracture of the ceramic core. This breakdown triggers persistent P0420 and P0430 catalyst efficiency fault codes, generates upstream backpressure that strangles exhaust scavenging, and can result in foul rotten-egg hydrogen sulfide odors or internal substrate rattle under load.

The Engineering Solution

Engineered as a direct-fit bolt-on assembly, this left and right manifold converter pair features high-grade stainless steel outer shells that resist road-salt corrosion and high-temperature oxidation. Inside, a durable ceramic honeycomb substrate provides optimal cell density (CPSI) to maximize surface area contact with exhaust gasses without creating restrictive backpressure. Heavy-gauge, precision-machined mounting flanges mate flush against the cylinder heads and downpipes to eliminate blow-by leaks, while integrated factory-location O2 sensor bungs preserve accurate downstream fuel-trim feedback to the engine control module.

What's Included

• 1x Front Left Exhaust Manifold Catalytic Converter
• 1x Front Right Exhaust Manifold Catalytic Converter
• Exhaust Installation Gaskets
• Installation Hardware

Technical Specifications

Compatibility

• 2005 Lexus GX470 Base Sport Utility 4.7L V8
• 2006 Lexus GX470 Base Sport Utility 4.7L V8
• 2007 Lexus GX470 Base Sport Utility 4.7L V8
• 2008 Lexus GX470 Base Sport Utility 4.7L V8
• 2009 Lexus GX470 Base Sport Utility 4.7L V8

Frequently Asked Questions & Fitment Warnings

Does this fit the J120 GX?

Yes, this is a direct fit for the 2005-2009 Lexus GX equipped with the 2UZ-FE 4.7L V8 engine. Not legal for sale or installation in California, Colorado, New York, or Maine.

Is welding or pipe cutting required for installation?

No, this unit utilizes OEM-style bolt-on flanges that mount directly to factory exhaust studs and downpipe connections without fabrication.

The Lexus Truck Durability

Built for the severe-duty demands of overland utility and heavy towing, this converter assembly restores critical low-end exhaust dynamics and structural exhaust integrity across rough terrain.