{"product_id":"performance-head-gasket-kit-for-chevrolet-avalanche-2004-2006-5-3l","title":"Performance Head Gasket Kit for Chevrolet Avalanche (2004-2006) 5.3L","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eHeavy-Duty Multi-Layer Steel Head Gasket Kit for 2004-2006 Chevrolet Avalanche (GMT805)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e The Performance Head Gasket Kit seals the combustion chambers and fluid galleries on 2004-2006 Chevrolet Avalanche 5.3L engines to prevent coolant cross-contamination and hold compression under high thermal stress.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock Chevrolet Avalanche Cylinder Head \u0026amp; Gasket Failure Modes\u003c\/h3\u003e\n\u003cp\u003eFactory composite gaskets on high-mileage \u003cstrong\u003eGMT805\u003c\/strong\u003e trucks running the \u003cstrong\u003eVortec 5300 LM7\/L59\u003c\/strong\u003e platform degrade from continuous thermal cycling and combustion scrub. Micro-fretting between the iron engine block and aluminum cylinder heads causes fire-ring degradation, external coolant leaks along the block deck, and oil contamination into coolant passages. Additionally, factory intake gaskets and aging valley cover seals harden over time, causing unmetered vacuum leaks and persistent lean codes (P0171\/P0174).\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThis master overhaul kit utilizes \u003cstrong\u003eMulti-Layer Steel (MLS)\u003c\/strong\u003e head gaskets engineered with tempered stainless steel outer layers and an elastomer coating to handle differential thermal expansion rates between cast-iron blocks and aluminum heads. The integrated combustion seal beads maintain high recovery under elevated cylinder pressures, preventing blowout under heavy towing loads. Paired with high-grade fluoroelastomer valve stem seals, silicone-beaded intake and oil pan gaskets, and precision knock sensor grommets, this complete overhaul package restores stoichiometric sealing integrity and crankcase vacuum retention.\u003c\/p\u003e\n\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e2 Multi-Layer Steel (MLS) Head Gaskets\u003c\/li\u003e\n  \u003cli\u003e1 Rear Crankshaft Gasket Seal\u003c\/li\u003e\n  \u003cli\u003e1 Engine Oil Pan Gasket\u003c\/li\u003e\n  \u003cli\u003e1 Valley Cover Gasket\u003c\/li\u003e\n  \u003cli\u003eIntake Manifold Gaskets\u003c\/li\u003e\n  \u003cli\u003eExhaust Manifold Gaskets\u003c\/li\u003e\n  \u003cli\u003eKnock Sensor Grommets\u003c\/li\u003e\n  \u003cli\u003eDamping Plug Heads\u003c\/li\u003e\n  \u003cli\u003eValve Stem Seals\u003c\/li\u003e\n  \u003cli\u003eFiber Base Plates\u003c\/li\u003e\n  \u003cli\u003eOther O-rings and Gaskets\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 Chevrolet Avalanche\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;\"\u003eVortec 5300 (LM7 \/ L59) \/ GMT805\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;\"\u003e295 hp \/ 335 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;\"\u003eCS9284, HS26191PT, HS26190PT-2, HS26191PT-1, HGS3168, ES72220, GS33449, HSGM10448L, LGS3165, MIS16340\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 Chevrolet Avalanche 1500 (5.3L V8)\u003c\/li\u003e\n  \u003cli\u003e2005 Chevrolet Avalanche 1500 (5.3L V8)\u003c\/li\u003e\n  \u003cli\u003e2006 Chevrolet Avalanche 1500 (5.3L V8)\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 GMT805 Avalanche?\u003c\/h4\u003e\n\u003cp\u003eYes, this is a direct fit for the 2004-2006 Chevrolet Avalanche equipped with the \u003cstrong\u003eVortec 5.3L V8\u003c\/strong\u003e engine. \u003cstrong\u003eNote: This kit is not intended for 8.1L big-block models, and piston rings are explicitly not included in this gasket set.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003ch4\u003eAre new cylinder head bolts required during this installation?\u003c\/h4\u003e\n\u003cp\u003eYes, the factory cylinder head bolts on Gen III Vortec engines are Torque-to-Yield (TTY) and cannot be reused under any circumstances.\u003c\/p\u003e\n\n\u003ch3\u003eThe Chevrolet Durability Standard\u003c\/h3\u003e\n\u003cp\u003eEngineered to handle severe-duty payload and towing conditions, this sealing system restores the structural resilience and heavy-duty reliability required of full-size GMT800-series utility platforms.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":67551497519352,"sku":"DS-EDX77D6VL","price":89.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/performance-head-gasket-kit-for-chevrolet-avalanche-2004-2006-5-3l-1.jpg?v=1790797632","url":"https:\/\/performancechiptuning.com\/products\/performance-head-gasket-kit-for-chevrolet-avalanche-2004-2006-5-3l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}