{"product_id":"catalytic-converter-for-hummer-h3-2006-3-5l-front","title":"Catalytic Converter for Hummer H3 (2006) 3.5L Front","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eDirect-Fit Front Exhaust Manifold Catalytic Converter for Hummer H3 (GMT345)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e The Front Exhaust Manifold Catalytic Converter replaces the compromised factory manifold converter on the Hummer H3 to eliminate catalyst-efficiency DTCs, reduce exhaust backpressure, and restore closed-loop emissions compliance.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock Hummer H3 Manifold Failure\u003c\/h3\u003e\n\u003cp\u003eThe factory integrated exhaust manifold converter on the \u003cstrong\u003eGMT345\u003c\/strong\u003e chassis experiences severe thermal cycling stress. Positioned directly against the cylinder head, the OE cast runners and internal ceramic substrate suffer from continuous heat soak and aggressive exhaust pulses from the inline-5 configuration. Over time, the factory ceramic washcoat degrades, triggering persistent P0420 catalyst efficiency trouble codes. Additionally, structural thermal expansion leads to hairline cracking across the manifold collector welds, causing raw exhaust leaks that disrupt upstream oxygen sensor feedback and throw off air-fuel trims.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThis front manifold assembly is engineered as a direct replacement utilizing heavy-gauge stainless steel tubular construction that resists thermal fatigue and stress cracking far better than rigid OE cast iron. Fitted with a high-efficiency ceramic substrate coated in targeted precious metals (platinum, palladium, and rhodium), it provides rapid light-off times and optimal conversion efficiency. Precision laser-cut flanges prevent mounting-face warpage under extreme cylinder-head temperatures, while mandrel-bent runners preserve uniform wall thickness to streamline exhaust scavenging directly off the exhaust ports to eliminate bottlenecks.\u003c\/p\u003e\n\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cdiv style=\"overflow-x: auto; margin-bottom: 20px;\"\u003e\n  \u003ctable width=\"100%\" style=\"border-collapse: collapse; border: 1px solid #e0e0e0; font-size: 14px; min-width: 300px;\"\u003e\n    \u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eFitment\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e2006 Hummer H3 3.5L\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eEngine \/ Chassis\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e\n\u003cstrong\u003eAtlas L52\u003c\/strong\u003e (3.5L I5) \/ \u003cstrong\u003eGMT345\u003c\/strong\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eStock Output\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e220 hp \/ 225 lb-ft\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eReplaces OEM Part #\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e\n\u003cstrong\u003e674-703\u003c\/strong\u003e, \u003cstrong\u003e16481\u003c\/strong\u003e, \u003cstrong\u003e3011026\u003c\/strong\u003e, \u003cstrong\u003e19214\u003c\/strong\u003e, \u003cstrong\u003eOPCG4041\u003c\/strong\u003e, \u003cstrong\u003e101433\u003c\/strong\u003e, \u003cstrong\u003e642196\u003c\/strong\u003e, \u003cstrong\u003e50428\u003c\/strong\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e2006 Hummer H3 Base Sport Utility 4-Door 3.5L 3460CC 211Cu. In. l5 GAS DOHC Naturally Aspirated\u003c\/li\u003e\n  \u003cli\u003e2006 Hummer H3 Adventure Sport Utility 4-Door 3.5L 3460CC 211Cu. In. l5 GAS DOHC Naturally Aspirated\u003c\/li\u003e\n  \u003cli\u003e2006 Hummer H3 Luxury Sport Utility 4-Door 3.5L 3460CC 211Cu. In. l5 GAS DOHC Naturally Aspirated\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003ch4\u003eDoes this fit the GMT345 H3?\u003c\/h4\u003e\n\u003cp\u003eYes, this is a direct fit for the 2006 Hummer H3 equipped with the \u003cstrong\u003eAtlas L52\u003c\/strong\u003e 3.5L engine.\u003c\/p\u003e\n\n\u003ch4\u003eIs this unit legal for sale and use in all 50 states?\u003c\/h4\u003e\n\u003cp\u003eNo, this is an EPA 46-state legal converter and cannot be legally registered, sold, or shipped to California, New York, Colorado, or Maine.\u003c\/p\u003e\n\n\u003ch3\u003eThe Hummer Off-Road Durability Standard\u003c\/h3\u003e\n\u003cp\u003eEngineered to handle severe trail washboards and high-load low-range crawling, this assembly provides the structural rigidity and thermal resistance necessary to keep your heavy-duty 4WD rig clear of emissions codes and operating at peak exhaust flow.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":67538031476984,"sku":"DS-EPIWRNZ0Q","price":141.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/catalytic-converter-for-hummer-h3-2006-3-5l-front-1.jpg?v=1790621149","url":"https:\/\/performancechiptuning.com\/fr\/products\/catalytic-converter-for-hummer-h3-2006-3-5l-front","provider":"Performance Chip Tuning","version":"1.0","type":"link"}