This High Flow Exhaust Manifold for 2017–2025 Chevy and GMC trucks equipped with the 6.6L Duramax L5P diesel is made from cast, high-sil moly and is engineered to improve exhaust flow, reduce restriction, and support better turbo response. The manifold and up-pipe exhaust system are designed to maximize power and flow characteristics, lower exhaust gas temperatures (EGTs) and accelerate turbo spool-up while increasing power, fuel economy, and maintaining reliability. Built for heavy-duty diesel use, this manifold is a reliable upgrade for replacing cracked, leaking, warped, or restrictive factory-style components and is suitable for daily driving, towing, hauling, and performance-focused Duramax applications.

Fitment

• 2017–2019 Chevrolet Silverado 2500/3500 HD -- 6.6L Duramax L5P
• 2017–2019 GMC Sierra 2500/3500 HD -- 6.6L Duramax L5P
• 2020–2025 Chevrolet Silverado 2500/3500 HD -- 6.6L Duramax L5P
• 2020–2025 GMC Sierra 2500/3500 HD -- 6.6L Duramax L5P

Product Details

• Material: Cast high-sil moly construction
• Up-Pipe Construction: Aircraft-grade 304 stainless steel bellows with internally sleeved design and increased inner diameter for higher flow
• Up-Pipe Wall Thickness: .120-inch wall thickness with 2-inch outside diameter
• Performance Benefits: Lowers exhaust gas temperatures (EGTs), accelerates turbo spool-up, and increases power and fuel economy
• EGT Port: Pre-molded and tapped for EGT gauge sensor installation
• Hardware: Includes 16 exhaust manifold mounting bolts

Installation

This is a direct-fit replacement for factory manifolds on 2017–2025 models. Professional installation is recommended to ensure proper sealing and turbo response optimization. Remove factory manifolds and bolt-on this high flow exhaust manifold assembly using OEM or upgraded fasteners.

Check local emissions regulations before purchase. Professional installation is recommended.

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