{"product_id":"exhaust-manifold-with-catalytic-converter-for-gmc-canyon-2004-2006-2-8l","title":"Exhaust Manifold with Catalytic Converter for GMC Canyon (2004-2006) 2.8L","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eDirect-Fit Replacement Exhaust Manifold with Catalytic Converter for 2004-2006 GMC Canyon (GMT355)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e The integrated exhaust manifold and catalytic converter replaces cracked factory exhaust runners and degraded catalyst substrates on the 2004-2006 Canyon to eliminate exhaust leaks, restore accurate O2 sensor feedback, and silence cold-start valvetrain ticking.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock GMC Canyon Exhaust Manifold Cracking Problem\u003c\/h3\u003e\n\u003cp\u003eThe factory cast iron manifold on the \u003cstrong\u003eGMT355\u003c\/strong\u003e chassis frequently succumbs to extreme thermal cycling and uneven expansion between the cylinder head and the catalytic assembly. Over time, hair-line fractures propagate across the exhaust runner junctions, causing high-frequency ticking on cold starts that partially subsides as the metal expands. More critically, unmetered atmospheric oxygen enters upstream of the pre-cat oxygen sensor through these fractures, skewing fuel trim data, causing rich\/lean diagnostic trouble codes (DTCs), raw exhaust smell in the cabin, and reduced low-end torque.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThis direct-fit replacement combines a precision-machined tubular stainless steel manifold with an integrated, EPA-compliant high-flow ceramic substrate catalytic converter. Stainless steel construction tolerates rapid thermal expansion without fatigue cracking, while uniform wall thickness stabilizes heat distribution across all primary runners. The assembly matches factory port geometries and OE mounting flanges exactly, eliminating the need for cutting or welding. By restoring an airtight seal and standard backpressure dynamics, it recovers lost cylinder scavenge efficiency and maintains consistent air-fuel ratios without triggering check engine lights.\u003c\/p\u003e\n\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1 Exhaust Manifold with Integrated Catalytic Converter\u003c\/li\u003e\n  \u003cli\u003eExhaust Manifold Gasket\u003c\/li\u003e\n  \u003cli\u003eDownpipe Flange Gasket\u003c\/li\u003e\n  \u003cli\u003eMounting Studs and Nuts\u003c\/li\u003e\n\u003c\/ul\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;\"\u003e2004-2006 GMC Canyon\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\u003eVortec 2800 (LK5)\u003c\/strong\u003e \/ \u003cstrong\u003eGMT355\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;\"\u003e175 hp \/ 185 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\u003e12595160\u003c\/strong\u003e, \u003cstrong\u003e12571604\u003c\/strong\u003e, \u003cstrong\u003e641216\u003c\/strong\u003e, \u003cstrong\u003e674851\u003c\/strong\u003e, \u003cstrong\u003e50458\u003c\/strong\u003e, \u003cstrong\u003e16612\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\u003e2004 GMC Canyon Base \/ SL \/ SLE 2.8L L4\u003c\/li\u003e\n  \u003cli\u003e2005 GMC Canyon Base \/ SL \/ SLE \/ Z71 \/ Z85 2.8L L4\u003c\/li\u003e\n  \u003cli\u003e2006 GMC Canyon SL \/ SLE \/ WT \/ Z71 \/ Z85 2.8L L4\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eFrequently Asked Questions \u0026amp; Fitment Warnings\u003c\/h3\u003e\n\u003ch4\u003eDoes this fit the GMT355 Canyon?\u003c\/h4\u003e\n\u003cp\u003eYes, this is a direct fit for the 2004-2006 GMC Canyon equipped with the \u003cstrong\u003eAtlas LK5 2.8L\u003c\/strong\u003e engine. \u003cstrong\u003eNon-CARB compliant: Not legal for sale or use in California, Colorado, New York, or Maine.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003ch4\u003eWhat are the proper installation torque sequences for this assembly?\u003c\/h4\u003e\n\u003cp\u003eClean the cylinder head thoroughly, torque fasteners progressively from the center outward to factory specifications, and re-torque all hardware following the initial heat cycle.\u003c\/p\u003e\n\n\u003ch3\u003eThe GMC Heavy-Duty Caliber\u003c\/h3\u003e\n\u003cp\u003eEngineered to handle sustained payload hauling and high thermal loads, this stainless steel assembly delivers durable reliability and structural integrity for hard-working midsize trucks.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":67896179523832,"sku":"DS-EOMSM7JRH","price":248.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/exhaust-manifold-with-catalytic-converter-for-gmc-canyon-2004-2006-2-8l-1.jpg?v=1793293551","url":"https:\/\/performancechiptuning.com\/de\/products\/exhaust-manifold-with-catalytic-converter-for-gmc-canyon-2004-2006-2-8l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}