Catalytic Converter for Toyota 4Runner (2003-2009) 4.0L

Direct-Fit Manifold Catalytic Converter Set for 2003-2009 Toyota 4Runner

What it Does: Replaces degraded factory exhaust manifolds and worn catalytic cores to clear P0420/P0430 DTCs and restore optimal exhaust gas scavenging.

The Stock 4Runner Catalyst Degradation and Thermal Fatigue

Factory exhaust manifolds on the 4th-generation N210 4Runner integrate the catalytic converters directly into the manifold runners. Over time, constant thermal cycling, towing loads, and vibration induce micro-fractures along the factory welds and collector seams. Concurrently, the OEM ceramic washcoat suffers thermal sintering and oil-vapor contamination, depleting oxygen storage capacity and triggering persistent catalyst efficiency check engine lights while choking high-RPM exhaust expulsion.

The Engineering Solution

Constructed from heavy-gauge stainless steel tubing, this direct-fit manifold converter pair resists thermal fatigue, oxidation, and road salt corrosion. High-efficiency ceramic monolith substrates maximize catalytic surface area to ensure rapid light-off and complete emissions conversion without generating restrictive exhaust backpressure. Precision laser-cut flanges prevent thermal warping, while factory-located O2 sensor bungs allow seamless plug-and-play installation utilizing the included gaskets and hardware.

Technical Specifications

Compatibility

• 2003 Toyota 4Runner 4.0L V6
• 2004 Toyota 4Runner 4.0L V6
• 2005 Toyota 4Runner 4.0L V6
• 2006 Toyota 4Runner 4.0L V6
• 2007 Toyota 4Runner 4.0L V6
• 2008 Toyota 4Runner 4.0L V6
• 2009 Toyota 4Runner 4.0L V6

The Toyota Truck Caliber

Engineered for high-mileage utility, this replacement assembly maintains the backpressure parameters necessary to safeguard low-end torque delivery during steep trail climbs and heavy trailer towing without recurring emissions faults.