Catalytic Converter for Isuzu I-370 (2007-2008) 3.7L Front

Direct-Fit Front Catalytic Converter for 2007-2008 Isuzu I-370 (GMT355)

What it Does: The Direct-Fit Front Catalytic Converter replaces the degraded factory manifold catalyst on the 2007-2008 Isuzu I-370 to eliminate P0420 diagnostic trouble codes and restore proper exhaust scavenging.

The Stock Isuzu I-370 Catalyst Breakdown

On the GMT355 platform running the LLR 3.7L inline-5, the close-coupled front manifold converter absorbs extreme thermal shock directly off the cylinder head. Over miles of heat cycling, the factory ceramic matrix degrades, leading to washcoat depletion, substrate micro-fracturing, and carbon contamination. This deterioration creates severe exhaust backpressure, robs engine torque, and triggers constant emissions fault codes.

The Engineering Solution

This replacement converter assembly is engineered with a high-efficiency ceramic honeycomb core washcoated in active precious metals to exceed standard EPA operating requirements. Encased in heavy-gauge, heat-resistant stainless steel, the assembly resists casing expansion and weld fatigue. Precision-stamped direct-fit mounting flanges bolt directly to the factory manifold and downstream exhaust system using OE interchange dimensions (16578, 641338, 19282), restoring exhaust flow without custom fabrication or cutting.

Technical Specifications

Compatibility

• 2007 Isuzu I-370 Extended Cab 3.7L L5
• 2007 Isuzu I-370 Crew Cab 3.7L L5
• 2008 Isuzu I-370 Extended Cab 3.7L L5
• 2008 Isuzu I-370 Crew Cab 3.7L L5

Frequently Asked Questions

Does this fit the GMT355 I-370?

Yes, this is a direct fit for the 2007-2008 Isuzu I-370 equipped with the LLR 3.7L engine.

Will this unit resolve a P0420 catalytic efficiency code?

Yes, replacing a degraded core with this unit restores converter oxidation thresholds to extinguish downstream O2 sensor fault codes when operating on a healthy engine.

The Isuzu Truck Durability Caliber

Engineered for midsize truck hauling and sustained payload demands, this direct-fit catalytic converter delivers the structural toughness and exhaust velocity required to keep your truck running clean under load.