{"product_id":"exhaust-kit-for-chevrolet-silverado-1998-1999-5-7l","title":"Exhaust Kit for Chevrolet Silverado (1998-1999) 5.7L","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eHigh-Flow Dual Muffler-Back Exhaust Kit for 1998-1999 Chevrolet Silverado (GMT400)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e The dual muffler-back exhaust kit replaces the restrictive factory single muffler and tailpipe assembly on the 1998-1999 Silverado to evacuate exhaust gases faster, reduce parasitic backpressure, and improve low-end towing torque.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock Chevrolet Silverado Exhaust Restriction\u003c\/h3\u003e\n\u003cp\u003eThe OEM exhaust routing on the \u003cstrong\u003eGMT400\u003c\/strong\u003e platform utilizes a heavy, baffled single-inlet muffler paired with restrictive crush-bent tubing. These factory bends narrow significantly at radius turns, disrupting exhaust gas velocity and trapping thermal energy near the rear axle. Under heavy load or sustained towing, the stock chambered configuration restricts volumetric efficiency on the \u003cstrong\u003eVortec 5700 L31\u003c\/strong\u003e small block, causing unnecessary exhaust gas recirculation in the cylinders, sluggish throttle response, and muted acoustics.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThis kit resolves upstream bottlenecks using a two-chambered \u003cstrong\u003eFlowmaster Super 44\u003c\/strong\u003e muffler featuring a single 3.0-inch inlet and dual 2.5-inch outlets to maximize scavenging dynamics. Fabricated from corrosion-resistant aluminized steel, the dual 2.5-inch tailpipes utilize smooth, CNC mandrel-bent routing that maintains cross-sectional diameter through every contour. The pipes route cleanly along the outside of the frame rails, engineered specifically with drop clearances for the factory spare tire and OEM receiver hitch while supporting all bed and cab wheelbases.\u003c\/p\u003e\n\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1 Flowmaster Super 44 muffler (single 3\" inlet, dual 2.5\" outlets)\u003c\/li\u003e\n  \u003cli\u003e2 aluminized mandrel-bent multi-piece 2.5\" tail pipes (slip-together)\u003c\/li\u003e\n  \u003cli\u003e8 muffler clamps\u003c\/li\u003e\n  \u003cli\u003e1 larger exhaust clamp\u003c\/li\u003e\n  \u003cli\u003e4 rubber-insulated hangers\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;\"\u003e1998-1999 Chevrolet Silverado (All Wheelbases)\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 5700 L31 \/ GMT400\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;\"\u003e255 hp \/ 330 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;\"\u003eN\/A\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\u003e1998 Chevrolet Silverado C\/K 1500 \/ 2500 \/ 3500 (5.7L V8 Gas, Single Inlet Muffler)\u003c\/li\u003e\n  \u003cli\u003e1999 Chevrolet Silverado 1500 \/ 2500 \/ 3500 Classic (5.7L V8 Gas, Single Inlet Muffler)\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 GMT400 Silverado?\u003c\/h4\u003e\n\u003cp\u003eYes, this is a direct fit for the 1998-1999 Chevrolet Silverado equipped with the \u003cstrong\u003eVortec 5700 L31\u003c\/strong\u003e 5.7L gasoline engine. \u003cstrong\u003eThis kit exclusively fits trucks equipped from the factory with a single-inlet muffler; it will not fit dual-inlet factory setups or models with aftermarket modified chassis configurations.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003ch4\u003eIs this exhaust system a direct bolt-on installation?\u003c\/h4\u003e\n\u003cp\u003eNo, this is a universal-fit muffler-back kit that requires an experienced installer or exhaust technician to trim or fabricate intermediate pipe connections forward of the muffler.\u003c\/p\u003e\n\n\u003ch3\u003eThe Chevrolet Heavy-Duty Caliber\u003c\/h3\u003e\n\u003cp\u003eEngineered to handle severe duty cycles, this system ensures your \u003cstrong\u003eGMT400\u003c\/strong\u003e retains the thermal durability and backpressure profile required for sustained towing, rough farm transit, and heavy payload demands without fracturing factory hanger brackets.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":67562640376056,"sku":"DS-E5NQOM0P1","price":377.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/exhaust-kit-for-chevrolet-silverado-1998-1999-5-7l-1.jpg?v=1790988470","url":"https:\/\/performancechiptuning.com\/products\/exhaust-kit-for-chevrolet-silverado-1998-1999-5-7l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}