2001-2004 GM 2500HD/3500HD 6.6L LB7 Duramax Exhaust Manifolds & Up-Pipes

Upgrade the performance of your 2001-2004 GM 6.6L Duramax with a top-quality exhaust manifold from Alligator Performance. Our manifolds are designed to provide significant gains in horsepower and torque by reducing back pressure, resulting in enhanced throttle response and unlocking the full potential of your 6.6L engine. Choose from a variety of designs, whether you’re after increased low-end power with a single-scroll manifold or improved top-end performance with a twin-scroll option. Discover the perfect match for your GM at Alligator Performance. Further enhance your diesels performance with Engine Upgrades!  GM Duramax Fitments: 2001, 2002, 2003, 2004 GM 6.6L Duramax. Submodel Fitments: WT, Custom, LT, LTZ, High Country, 1LT, 2LT, Pro, SLE, SLT, AT4, Denali. Some exceptions apply, please see individual product pages for specific fitments.