{"product_id":"high-flow-exhaust-manifold-and-up-pipes-for-gmc-sierra-2017-2025-6-6l-diesel","title":"High Flow Exhaust Manifold and Up Pipes for GMC Sierra (2017-2025) 6.6L Diesel","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eHigh-Flow Sil-Moly Exhaust Manifolds and Up Pipes for 2017-2025 GMC Sierra (K2XX \/ T1XX)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e The High Flow Exhaust Manifold and Up Pipe Kit replaces restrictive factory manifolds and failure-prone OEM up-pipes on the 2017-2025 GMC Sierra 6.6L Duramax to lower exhaust gas temperatures (EGTs) and accelerate turbo spool under load.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock GMC Sierra L5P Exhaust Bottleneck\u003c\/h3\u003e\n\u003cp\u003eFactory exhaust manifolds on the \u003cstrong\u003eDuramax L5P\u003c\/strong\u003e platform utilize restrictive cast geometries with pinched runner profiles designed to clear chassis constraints rather than optimize gas velocity. Over repeated heavy-load towing cycles, standard OEM up-pipe bellows develop fatigue cracks due to high thermal expansion and drive pressure. These exhaust leaks bleed turbine energy, elevate pre-turbo backpressure, raise baseline EGTs, and cause sluggish turbocharger response.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eCast from high-silicon molybdenum (\u003cstrong\u003esil-moly\u003c\/strong\u003e) ductile iron, these performance exhaust manifolds resist thermal fatigue, structural cracking, and flange warping under prolonged extreme heat. The paired heavy-gauge up-pipes feature internally sleeved \u003cstrong\u003e304 stainless steel\u003c\/strong\u003e expansion bellows that isolate chassis vibration while shielding the flex joints from hot exhaust velocity. Precision CNC-machined port entries and enlarged primary runners balance exhaust flow between cylinder banks, optimizing drive pressure and reducing parasitic pumping losses into the variable geometry turbocharger.\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;\"\u003e2017-2025 GMC Sierra 2500HD \/ 3500HD\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\u003eDuramax L5P\u003c\/strong\u003e (6.6L Diesel) \/ \u003cstrong\u003eK2XX \/ T1XX\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;\"\u003e445–470 hp \/ 910–975 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;\"\u003eDD448, DD508\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\u003e2017-2019 GMC Sierra 2500HD \/ 3500HD (6.6L Duramax L5P Turbo Diesel)\u003c\/li\u003e\n  \u003cli\u003e2020-2025 GMC Sierra 2500HD \/ 3500HD (6.6L Duramax L5P Turbo Diesel)\u003c\/li\u003e\n  \u003cli\u003eNote: Specifically engineered for the L5P platform; does not fit LB7, LLY, LBZ, LMM, or LML engines.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003ch4\u003eDoes this fit the K2XX \/ T1XX Sierra?\u003c\/h4\u003e\n\u003cp\u003eYes, this is a direct fit for the 2017-2025 GMC Sierra equipped with the \u003cstrong\u003eDuramax L5P\u003c\/strong\u003e engine.\u003c\/p\u003e\n\n\u003ch4\u003eIs aftermarket ECU tuning required for this manifold kit?\u003c\/h4\u003e\n\u003cp\u003eNo tuning is required, as the manifolds and up-pipes retain standard exhaust geometry and preserve all factory sensor and emissions systems.\u003c\/p\u003e\n\n\u003ch3\u003eThe GMC Heavy Duty Towing Standard\u003c\/h3\u003e\n\u003cp\u003eEngineered to withstand the demanding thermal cycles of commercial hauling and fifth-wheel towing, this exhaust assembly eliminates factory bellows failure while preserving turbo drive pressure on your heavy-duty Sierra.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":67541212201208,"sku":"DS-ESWPXISA6","price":1039.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/high-flow-exhaust-manifold-and-up-pipes-for-gmc-sierra-2017-2025-6-6l-diesel-1.jpg?v=1790663443","url":"https:\/\/performancechiptuning.com\/es\/products\/high-flow-exhaust-manifold-and-up-pipes-for-gmc-sierra-2017-2025-6-6l-diesel","provider":"Performance Chip Tuning","version":"1.0","type":"link"}